CVE-2021-29991
published 2021-11-03CVE-2021-29991: Firefox incorrectly accepted a newline in a HTTP/3 header, interpretting it as two separate headers. This allowed for a header splitting attack against servers…
PriorityP338high8.1CVSS 3.1
AVNACLPRNUIRSUCHIHAN
EPSS
0.89%
54.8th percentile
Firefox incorrectly accepted a newline in a HTTP/3 header, interpretting it as two separate headers. This allowed for a header splitting attack against servers using HTTP/3. This vulnerability affects Firefox < 91.0.1 and Thunderbird < 91.0.1.
Affected
10 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | firefox | < firefox 91.0.1-1 (sid) | firefox 91.0.1-1 (sid) |
| mozilla | firefox | < 91.0.1 | 91.0.1 |
| mozilla | firefox | — | — |
| mozilla | firefox | >= 0 < 91.0.1+build1-0ubuntu0.18.04.1 | 91.0.1+build1-0ubuntu0.18.04.1 |
| mozilla | firefox | >= 0 < 91.0.1+build1-0ubuntu0.20.04.1 | 91.0.1+build1-0ubuntu0.20.04.1 |
| mozilla | firefox | >= unspecified < 91.0.1 | 91.0.1 |
| mozilla | thunderbird | < 91.0.1 | 91.0.1 |
| mozilla | thunderbird | >= 0 < 1:91.5.0+build1-0ubuntu0.18.04.1 | 1:91.5.0+build1-0ubuntu0.18.04.1 |
| mozilla | thunderbird | >= 0 < 1:91.5.0+build1-0ubuntu0.20.04.1 | 1:91.5.0+build1-0ubuntu0.20.04.1 |
| mozilla | thunderbird | >= unspecified < 91.0.1 | 91.0.1 |
CVSS provenance
nvdv3.18.1HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N
nvdv2.05.8MEDIUMAV:N/AC:M/Au:N/C:P/I:P/A:N
osv8.8HIGH
vendor_ubuntu8.8HIGH
vendor_debian8.1HIGH
vendor_redhat8.1HIGH
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Ubuntu
Thunderbird vulnerabilities
vendor_ubuntu·2022-01-21·CVSS 8.8
CVE-2022-22742 [HIGH] Thunderbird vulnerabilities
Title: Thunderbird vulnerabilities
Summary: Several security issues were fixed in Thunderbird.
Multiple security issues were discovered in Thunderbird. If a user were
tricked into opening a specially crafted website in a browsing context, an
attacker could potentially exploit these to cause a denial of service,
obtain sensitive information, trick a user into accepting unwanted
permissions, conduct header splitting attacks, conduct spoofing attacks,
bypass security restrictions, confuse the user, or execute arbitrary code.
(CVE-2021-4129, CVE-2021-4140, CVE-2021-29981, CVE-2021-29982,
CVE-2021-29987, CVE-2021-29991, CVE-2021-38495, CVE-2021-38496,
CVE-2021-38497, CVE-2021-38498, CVE-2021-38500, CVE-2021-38501,
CVE-2021-38503, CVE-2021-38504, CVE-2021-38506, CVE-2021-38507,
CVE-2021-38508,
Ubuntu
Firefox vulnerability
vendor_ubuntu·2021-08-19
CVE-2021-29991 Firefox vulnerability
Title: Firefox vulnerability
Summary: Firefox could be made to incorrectly accept newlines in HTTP/3 response
headers.
It was discovered that Firefox could be made to incorrectly accept
newlines in HTTP/3 response headers. If a user were tricked into
opening a specially crafted website, an attacker could exploit this
to conduct header splitting attacks.
Instructions: After a standard system update you need to restart Firefox to make
all the necessary changes.
Red Hat
Mozilla: Header Splitting possible with HTTP/3 Responses
vendor_redhat·2021-08-18·CVSS 8.1
CVE-2021-29991 [HIGH] CWE-79 Mozilla: Header Splitting possible with HTTP/3 Responses
Mozilla: Header Splitting possible with HTTP/3 Responses
Firefox incorrectly accepted a newline in a HTTP/3 header, interpretting it as two separate headers. This allowed for a header splitting attack against servers using HTTP/3. This vulnerability affects Firefox < 91.0.1 and Thunderbird < 91.0.1.
The Mozilla Foundation Security Advisory describes this flaw as:
Firefox incorrectly accepted a newline in a HTTP/3 header, interpretting it as two separate headers. This allowed for a header splitting attack against servers using HTTP/3.
Package: firefox (Red Hat Enterprise Linux 6) - Out of support scope
Package: thunderbird (Red Hat Enterprise Linux 6) - Out of support scope
Package: firefox (Red Hat Enterprise Linux 7) - Fix deferred
Package: thunderbird (Red Hat Enterprise Linux 7) -
Debian
CVE-2021-29991: firefox - Firefox incorrectly accepted a newline in a HTTP/3 header, interpretting it as t...
vendor_debian·2021·CVSS 8.1
CVE-2021-29991 [HIGH] CVE-2021-29991: firefox - Firefox incorrectly accepted a newline in a HTTP/3 header, interpretting it as t...
Firefox incorrectly accepted a newline in a HTTP/3 header, interpretting it as two separate headers. This allowed for a header splitting attack against servers using HTTP/3. This vulnerability affects Firefox < 91.0.1 and Thunderbird < 91.0.1.
Scope: local
sid: resolved (fixed in 91.0.1-1)
Mozilla
Mozilla Foundation Security Advisory 2021-37: CVE-2021-29991
vendor_mozilla·CVSS 8.1
CVE-2021-29991 [HIGH] Mozilla Foundation Security Advisory 2021-37: CVE-2021-29991
Mozilla Foundation Security Advisory 2021-37
CVE: CVE-2021-29991
Product: Firefox, Thunderbird
Impact: high
Fixed in: Firefox 91.0.1
Thunderbird 91.0.1
GHSA
GHSA-8p2q-73gc-fxq5: Firefox incorrectly accepted a newline in a HTTP/3 header, interpretting it as two separate headers
ghsa_unreviewed·2022-05-24
CVE-2021-29991 [HIGH] CWE-444 GHSA-8p2q-73gc-fxq5: Firefox incorrectly accepted a newline in a HTTP/3 header, interpretting it as two separate headers
Firefox incorrectly accepted a newline in a HTTP/3 header, interpretting it as two separate headers. This allowed for a header splitting attack against servers using HTTP/3. This vulnerability affects Firefox < 91.0.1 and Thunderbird < 91.0.1.
OSV
thunderbird vulnerabilities
osv·2022-01-21·CVSS 8.8
CVE-2021-4129 [HIGH] thunderbird vulnerabilities
thunderbird vulnerabilities
Multiple security issues were discovered in Thunderbird. If a user were
tricked into opening a specially crafted website in a browsing context, an
attacker could potentially exploit these to cause a denial of service,
obtain sensitive information, trick a user into accepting unwanted
permissions, conduct header splitting attacks, conduct spoofing attacks,
bypass security restrictions, confuse the user, or execute arbitrary code.
(CVE-2021-4129, CVE-2021-4140, CVE-2021-29981, CVE-2021-29982,
CVE-2021-29987, CVE-2021-29991, CVE-2021-38495, CVE-2021-38496,
CVE-2021-38497, CVE-2021-38498, CVE-2021-38500, CVE-2021-38501,
CVE-2021-38503, CVE-2021-38504, CVE-2021-38506, CVE-2021-38507,
CVE-2021-38508, CVE-2021-38509, CVE-2021-43534, CVE-2021-43535,
CVE-2021-43536, CVE
OSV
CVE-2021-29991: Firefox incorrectly accepted a newline in a HTTP/3 header, interpretting it as two separate headers
osv·2021-08-18·CVSS 8.1
CVE-2021-29991 [HIGH] CVE-2021-29991: Firefox incorrectly accepted a newline in a HTTP/3 header, interpretting it as two separate headers
Firefox incorrectly accepted a newline in a HTTP/3 header, interpretting it as two separate headers. This allowed for a header splitting attack against servers using HTTP/3. This vulnerability affects Firefox < 91.0.1 and Thunderbird < 91.0.1.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2021-11-03
Published