CVE-2021-43565
published 2022-09-06CVE-2021-43565: The x/crypto/ssh package before 0.0.0-20211202192323-5770296d904e of golang.org/x/crypto allows an attacker to panic an SSH server.
PriorityP336high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
0.95%
56.7th percentile
The x/crypto/ssh package before 0.0.0-20211202192323-5770296d904e of golang.org/x/crypto allows an attacker to panic an SSH server.
Affected
10 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | golang-go.crypto | < golang-go.crypto 1:0.0~git20211202.5770296-1 (bookworm) | golang-go.crypto 1:0.0~git20211202.5770296-1 (bookworm) |
| golang.org | x_crypto | >= 0 < 0.0.0-20211202192323-5770296d904e | 0.0.0-20211202192323-5770296d904e |
| golang | ssh | < 0.0.0-20211202192323-5770296d904e | 0.0.0-20211202192323-5770296d904e |
| msrc | cbl2_cf-cli_8.4.0-24_on_cbl_mariner_2.0 | — | — |
| msrc | cbl2_cri-o_1.22.3-14_on_cbl_mariner_2.0 | — | — |
| msrc | cbl2_gh_2.13.0-24_on_cbl_mariner_2.0 | — | — |
| msrc | cbl2_libcontainers-common_20210626-7_on_cbl_mariner_2.0 | — | — |
| msrc | cbl2_moby-buildx_0.7.1-24_on_cbl_mariner_2.0 | — | — |
| msrc | cbl_mariner_2.0_arm | — | — |
| msrc | cbl_mariner_2.0_x64 | — | — |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
osv7.5HIGH
vendor_debian7.5HIGH
vendor_msrc7.5HIGH
vendor_redhat7.5HIGH
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Microsoft
The x/crypto/ssh package before 0.0.0-20211202192323-5770296d904e of golang.org/x/crypto allows an attacker to panic an SSH server.
vendor_msrc·2022-09-13·CVSS 7.5
CVE-2021-43565 [HIGH] The x/crypto/ssh package before 0.0.0-20211202192323-5770296d904e of golang.org/x/crypto allows an attacker to panic an SSH server.
The x/crypto/ssh package before 0.0.0-20211202192323-5770296d904e of golang.org/x/crypto allows an attacker to panic an SSH server.
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
mitre: mitre
Customer Actio
Red Hat
golang.org/x/crypto: empty plaintext packet causes panic
vendor_redhat·2021-12-02·CVSS 7.5
CVE-2021-43565 [HIGH] CWE-20 golang.org/x/crypto: empty plaintext packet causes panic
golang.org/x/crypto: empty plaintext packet causes panic
The x/crypto/ssh package before 0.0.0-20211202192323-5770296d904e of golang.org/x/crypto allows an attacker to panic an SSH server.
There's an input validation flaw in golang.org/x/crypto's readCipherPacket() function. An unauthenticated attacker who sends an empty plaintext packet to a program linked with golang.org/x/crypto/ssh could cause a panic, potentially leading to denial of service.
Statement: go-toolset shipped with Red Hat Developer Tools - Compilers and golang shipped with Red Hat Enterprise Linux 8 are not affected by this flaw because they do not ship the vulnerable code.
This flaw was rated to have a Moderate impact because it is not shipped in the Golang standard library and thus has a reduced impact to products co
Debian
CVE-2021-43565: golang-go.crypto - The x/crypto/ssh package before 0.0.0-20211202192323-5770296d904e of golang.org/...
vendor_debian·2021·CVSS 7.5
CVE-2021-43565 [HIGH] CVE-2021-43565: golang-go.crypto - The x/crypto/ssh package before 0.0.0-20211202192323-5770296d904e of golang.org/...
The x/crypto/ssh package before 0.0.0-20211202192323-5770296d904e of golang.org/x/crypto allows an attacker to panic an SSH server.
Scope: local
bookworm: resolved (fixed in 1:0.0~git20211202.5770296-1)
bullseye: open
forky: resolved (fixed in 1:0.0~git20211202.5770296-1)
sid: resolved (fixed in 1:0.0~git20211202.5770296-1)
trixie: resolved (fixed in 1:0.0~git20211202.5770296-1)
OSV
Panic on malformed packets in golang.org/x/crypto/ssh
osv·2022-09-13
CVE-2021-43565 Panic on malformed packets in golang.org/x/crypto/ssh
Panic on malformed packets in golang.org/x/crypto/ssh
Unauthenticated clients can cause a panic in SSH servers.
When using AES-GCM or ChaCha20Poly1305, consuming a malformed packet which contains an empty plaintext causes a panic.
OSV
x/crypto/ssh vulnerable to panic via malformed packets
osv·2022-09-07
CVE-2021-43565 [HIGH] x/crypto/ssh vulnerable to panic via malformed packets
x/crypto/ssh vulnerable to panic via malformed packets
The x/crypto/ssh package before 0.0.0-20211202192323-5770296d904e of golang.org/x/crypto allows an unauthenticated attacker to panic an SSH server. When using AES-GCM or ChaCha20Poly1305, consuming a malformed packet which contains an empty plaintext causes a panic.
GHSA
x/crypto/ssh vulnerable to panic via malformed packets
ghsa·2022-09-07
CVE-2021-43565 [HIGH] x/crypto/ssh vulnerable to panic via malformed packets
x/crypto/ssh vulnerable to panic via malformed packets
The x/crypto/ssh package before 0.0.0-20211202192323-5770296d904e of golang.org/x/crypto allows an unauthenticated attacker to panic an SSH server. When using AES-GCM or ChaCha20Poly1305, consuming a malformed packet which contains an empty plaintext causes a panic.
OSV
CVE-2021-43565: The x/crypto/ssh package before 0
osv·2022-09-06·CVSS 7.5
CVE-2021-43565 [HIGH] CVE-2021-43565: The x/crypto/ssh package before 0
The x/crypto/ssh package before 0.0.0-20211202192323-5770296d904e of golang.org/x/crypto allows an attacker to panic an SSH server.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2022-09-06
Published