CVE-2021-4044
published 2021-12-14CVE-2021-4044: Internally libssl in OpenSSL calls X509_verify_cert() on the client side to verify a certificate supplied by a server. That function may return a negative…
PriorityP355high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
50.10%
98.8th percentile
Internally libssl in OpenSSL calls X509_verify_cert() on the client side to verify a certificate supplied by a server. That function may return a negative return value to indicate an internal error (for example out of memory). Such a negative return value is mishandled by OpenSSL and will cause an IO function (such as SSL_connect() or SSL_do_handshake()) to not indicate success and a subsequent call to SSL_get_error() to return the value SSL_ERROR_WANT_RETRY_VERIFY. This return value is only supposed to be returned by OpenSSL if the application has previously called SSL_CTX_set_cert_verify_callback(). Since most applications do not do this the SSL_ERROR_WANT_RETRY_VERIFY return value from SSL_get_error() will be totally unexpected and applications may not behave correctly as a result. The exact behaviour will depend on the application but it could result in crashes, infinite loops or other similar incorrect responses. This issue is made more serious in combination with a separate bug in OpenSSL 3.0 that will cause X509_verify_cert() to indicate an internal error when processing a certificate chain. This will occur where a certificate does not include the Subject Alternative Name extension but where a Certificate Authority has enforced name constraints. This issue can occur even with valid chains. By combining the two issues an attacker could induce incorrect, application dependent behaviour. Fixed in OpenSSL 3.0.1 (Affected 3.0.0).
Affected
14 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | openssl | — | — |
| nodejs | node.js | >= 17.0.0 < 17.3.0 | 17.3.0 |
| openssl | openssl | < 1.0.2 | 1.0.2 |
| openssl | openssl | — | — |
| openssl | openssl | — | — |
| openssl | openssl | — | — |
| openssl | openssl | >= 0 < 3.0.1-r0 | 3.0.1-r0 |
| openssl | openssl | >= 0 < 3.0.1-r0 | 3.0.1-r0 |
| openssl | openssl | >= 0 < 3.0.1-r0 | 3.0.1-r0 |
| openssl | openssl | >= 0 < 3.0.1-r0 | 3.0.1-r0 |
| openssl | openssl | >= 0 < 3.0.1-r0 | 3.0.1-r0 |
| openssl | openssl | >= 0 < 3.0.1-r0 | 3.0.1-r0 |
| openssl | openssl | >= 0 < 3.0.1-r0 | 3.0.1-r0 |
| paloalto | pan-os | — | — |
Detection & IOCsextracted from sources · hover to see the quote
- →Affected version is exclusively OpenSSL 3.0.0 SSL/TLS clients; presence of this version in an environment indicates exposure to CVE-2021-4044 ↗
- →Trigger condition: a certificate chain where the certificate lacks the Subject Alternative Name extension AND a CA has enforced name constraints — this causes X509_verify_cert() to return an internal error, which combined with the mishandling bug can be used to induce incorrect application behaviour ↗
- →Observable symptom for detection: an SSL/TLS client application returning SSL_ERROR_WANT_RETRY_VERIFY from SSL_get_error() without having registered SSL_CTX_set_cert_verify_callback() is a strong indicator of exploitation or triggering of this bug ↗
- →Behavioural indicators of exploitation include application crashes, infinite loops, or other anomalous responses in OpenSSL 3.0.0 TLS clients during certificate verification ↗
- ·Only OpenSSL 3.0.0 is affected; OpenSSL 1.1.1 and 1.0.2 are explicitly NOT affected, so detections should be scoped to environments running OpenSSL 3.0.0 ↗
- ·Red Hat shipped versions of OpenSSL (RHEL 6, 7, 8, 9, JBoss, etc.) are all confirmed not affected — do not flag these as vulnerable ↗
- ·The vulnerability is client-side only; libssl calls X509_verify_cert() on the client side during server certificate verification — server-side OpenSSL instances are not the attack surface ↗
- ·The bug is most dangerous when combined with a second OpenSSL 3.0 bug (missing SAN + CA name constraints); either bug alone has reduced impact ↗
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P
osv7.5HIGH
vendor_debian7.5LOW
vendor_redhat7.5HIGH
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GHSA
Invalid handling of `X509_verify_cert()` internal errors in libssl
ghsa·2021-12-15
CVE-2021-4044 [HIGH] CWE-835 Invalid handling of `X509_verify_cert()` internal errors in libssl
Invalid handling of `X509_verify_cert()` internal errors in libssl
Internally libssl in OpenSSL calls X509_verify_cert() on the client side to verify a certificate supplied by a server. That function may return a negative return value to indicate an internal error (for example out of memory). Such a negative return value is mishandled by OpenSSL and will cause an IO function (such as SSL_connect() or SSL_do_handshake()) to not indicate success and a subsequent call to SSL_get_error() to return the value SSL_ERROR_WANT_RETRY_VERIFY. This return value is only supposed to be returned by OpenSSL if the application has previously called SSL_CTX_set_cert_verify_callback(). Since most applications do not do this the SSL_ERROR_WANT_RETRY_VERIFY return value from SSL_get_error() will be totally un
OSV
Invalid handling of `X509_verify_cert()` internal errors in libssl
osv·2021-12-15
CVE-2021-4044 [HIGH] Invalid handling of `X509_verify_cert()` internal errors in libssl
Invalid handling of `X509_verify_cert()` internal errors in libssl
Internally libssl in OpenSSL calls X509_verify_cert() on the client side to verify a certificate supplied by a server. That function may return a negative return value to indicate an internal error (for example out of memory). Such a negative return value is mishandled by OpenSSL and will cause an IO function (such as SSL_connect() or SSL_do_handshake()) to not indicate success and a subsequent call to SSL_get_error() to return the value SSL_ERROR_WANT_RETRY_VERIFY. This return value is only supposed to be returned by OpenSSL if the application has previously called SSL_CTX_set_cert_verify_callback(). Since most applications do not do this the SSL_ERROR_WANT_RETRY_VERIFY return value from SSL_get_error() will be totally un
OSV
Invalid handling of `X509_verify_cert()` internal errors in libssl
osv·2021-12-14
CVE-2021-4044 Invalid handling of `X509_verify_cert()` internal errors in libssl
Invalid handling of `X509_verify_cert()` internal errors in libssl
Internally libssl in OpenSSL calls `X509_verify_cert()` on the client side to
verify a certificate supplied by a server. That function may return a negative
return value to indicate an internal error (for example out of memory). Such a
negative return value is mishandled by OpenSSL and will cause an IO function
(such as `SSL_connect()` or `SSL_do_handshake()`) to not indicate success and a
subsequent call to `SSL_get_error()` to return the value
`SSL_ERROR_WANT_RETRY_VERIFY`. This return value is only supposed to be returned
by OpenSSL if the application has previously called
`SSL_CTX_set_cert_verify_callback()`. Since most applications do not do this the
`SSL_ERROR_WANT_RETRY_VERIFY` return value from `SSL_get_error()` wi
OSV
CVE-2021-4044: Internally libssl in OpenSSL calls X509_verify_cert() on the client side to verify a certificate supplied by a server
osv·2021-12-14·CVSS 7.5
CVE-2021-4044 [HIGH] CVE-2021-4044: Internally libssl in OpenSSL calls X509_verify_cert() on the client side to verify a certificate supplied by a server
Internally libssl in OpenSSL calls X509_verify_cert() on the client side to verify a certificate supplied by a server. That function may return a negative return value to indicate an internal error (for example out of memory). Such a negative return value is mishandled by OpenSSL and will cause an IO function (such as SSL_connect() or SSL_do_handshake()) to not indicate success and a subsequent call to SSL_get_error() to return the value SSL_ERROR_WANT_RETRY_VERIFY. This return value is only supposed to be returned by OpenSSL if the application has previously called SSL_CTX_set_cert_verify_callback(). Since most applications do not do this the SSL_ERROR_WANT_RETRY_VERIFY return value from SSL_get_error() will be totally unexpected and applications may not behave correctly as a result. The
Palo Alto
PAN-SA-2024-0008 Informational Bulletin: Impact of OSS CVEs in PAN-OS
vendor_paloalto·2024-09-04·CVSS 6.0
CVE-2010-1622 [MEDIUM] PAN-SA-2024-0008 Informational Bulletin: Impact of OSS CVEs in PAN-OS
PAN-SA-2024-0008 Informational Bulletin: Impact of OSS CVEs in PAN-OS
The Palo Alto Networks Product Security Assurance team has evaluated the following open source software (OSS) CVEs as they relate to PAN-OS software. While PAN-OS software may include the
CVEs: CVE-2010-1622, CVE-2015-7552, CVE-2018-16840, CVE-2019-7639, CVE-2020-17049, CVE-2020-7774, CVE-2021-0131, CVE-2021-0132, CVE-2021-0133, CVE-2021-0134, CVE-2021-4044, CVE-2021-4160, CVE-2021-41773, CVE-2022-1343, CVE-2022-21449, CVE-2022-2274, CVE-2022-22963, CVE-2022-22965, CVE-2022-24697, CVE-2022-32207, CVE-2022-3358, CVE-2022-3996, CVE-2022-40664, CVE-2022-44792, CVE-2022-44793, CVE-2023-1255, CVE-2023-22809, CVE-2023-23919, CVE-2023-3341, CVE-2023-4236, CVE-2023-4863, CVE-2023-51767
Affected products: PAN-OS
Palo Alto
PAN-SA-2024-0008 Informational Bulletin: Impact of OSS CVEs in PAN-OS
vendor_paloalto·2024-09-04·CVSS 6.0
CVE-2022-22965 [MEDIUM] PAN-SA-2024-0008 Informational Bulletin: Impact of OSS CVEs in PAN-OS
PAN-SA-2024-0008 Informational Bulletin: Impact of OSS CVEs in PAN-OS
The Palo Alto Networks Product Security Assurance team has evaluated the following open source software (OSS) CVEs as they relate to PAN-OS software. While PAN-OS software may include the
CVEs: CVE-2010-1622, CVE-2015-7552, CVE-2018-16840, CVE-2019-7639, CVE-2020-17049, CVE-2020-7774, CVE-2021-0131, CVE-2021-0132, CVE-2021-0133, CVE-2021-0134, CVE-2021-4044, CVE-2021-4160, CVE-2021-41773, CVE-2022-1343, CVE-2022-21449, CVE-2022-2274, CVE-2022-22963, CVE-2022-22965, CVE-2022-24697, CVE-2022-32207, CVE-2022-3358, CVE-2022-3996, CVE-2022-40664, CVE-2022-44792, CVE-2022-44793, CVE-2023-1255, CVE-2023-22809, CVE-2023-23919, CVE-2023-3341, CVE-2023-4236, CVE-2023-4863, CVE-2023-51767
Affected products: PAN-OS
Red Hat
openssl: invalid handling of X509_verify_cert() internal errors in libssl
vendor_redhat·2021-12-14·CVSS 7.5
CVE-2021-4044 [HIGH] CWE-252 openssl: invalid handling of X509_verify_cert() internal errors in libssl
openssl: invalid handling of X509_verify_cert() internal errors in libssl
Internally libssl in OpenSSL calls X509_verify_cert() on the client side to verify a certificate supplied by a server. That function may return a negative return value to indicate an internal error (for example out of memory). Such a negative return value is mishandled by OpenSSL and will cause an IO function (such as SSL_connect() or SSL_do_handshake()) to not indicate success and a subsequent call to SSL_get_error() to return the value SSL_ERROR_WANT_RETRY_VERIFY. This return value is only supposed to be returned by OpenSSL if the application has previously called SSL_CTX_set_cert_verify_callback(). Since most applications do not do this the SSL_ERROR_WANT_RETRY_VERIFY return value from SSL_get_error() will be tot
Debian
CVE-2021-4044: openssl - Internally libssl in OpenSSL calls X509_verify_cert() on the client side to veri...
vendor_debian·2021·CVSS 7.5
CVE-2021-4044 [HIGH] CVE-2021-4044: openssl - Internally libssl in OpenSSL calls X509_verify_cert() on the client side to veri...
Internally libssl in OpenSSL calls X509_verify_cert() on the client side to verify a certificate supplied by a server. That function may return a negative return value to indicate an internal error (for example out of memory). Such a negative return value is mishandled by OpenSSL and will cause an IO function (such as SSL_connect() or SSL_do_handshake()) to not indicate success and a subsequent call to SSL_get_error() to return the value SSL_ERROR_WANT_RETRY_VERIFY. This return value is only supposed to be returned by OpenSSL if the application has previously called SSL_CTX_set_cert_verify_callback(). Since most applications do not do this the SSL_ERROR_WANT_RETRY_VERIFY return value from SSL_get_error() will be totally unexpected and applications may not behave correctly as a result. The
No detection rules found.
No public exploits indexed.
HackerOne
Invalid handling of X509_verify_cert() internal errors in libssl (CVE-2021-4044)
hackerone·2022-01-20·CVSS 7.5
CVE-2021-4044 [HIGH] Invalid handling of X509_verify_cert() internal errors in libssl (CVE-2021-4044)
Invalid handling of X509_verify_cert() internal errors in libssl (CVE-2021-4044)
Internally libssl in OpenSSL calls X509_verify_cert() on the client side to
verify a certificate supplied by a server. That function may return a negative
return value to indicate an internal error (for example out of memory). Such a
negative return value is mishandled by OpenSSL and will cause an IO function
(such as SSL_connect() or SSL_do_handshake()) to not indicate success and a
subsequent call to SSL_get_error() to return the value
SSL_ERROR_WANT_RETRY_VERIFY. This return value is only supposed to be returned
by OpenSSL if the application has previously called
SSL_CTX_set_cert_verify_callback(). Since most applications do not do this the
SSL_ERROR_WANT_RETRY_VERIFY return value from SSL_get_error() will
Checkpoint
29th November – Threat Intelligence Report
blogs_checkpoint·2021-11-29·CVSS 7.5
CVE-2021-40444 [HIGH] 29th November – Threat Intelligence Report
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## 29th November – Threat Intelligence Report
For the latest discoveries in cyber research for the week of 29th November, please download our Threat Intelligence Bulletin .
Top Attacks and Breaches
GoDaddy has announced they suffered a data breach with data of up to 1.2 million of its customers being exposed after an unauthorized person used a compromised password to gain access to the company’s Managed WordPress hosting environment.
Iranian airline Mahan Air has been victim of a cyber-attack which resulted in it
https://git.openssl.org/gitweb/?p=openssl.git%3Ba=commitdiff%3Bh=758754966791c537ea95241438454aa86f91f256https://security.netapp.com/advisory/ntap-20211229-0003/https://www.openssl.org/news/secadv/20211214.txthttps://git.openssl.org/gitweb/?p=openssl.git%3Ba=commitdiff%3Bh=758754966791c537ea95241438454aa86f91f256https://security.netapp.com/advisory/ntap-20211229-0003/https://www.openssl.org/news/secadv/20211214.txt
2021-12-14
Published