Low severity · published Oct 28, 2026
CVE-2026-118372
LibreSSL ocspcheck through 4.4.0 CRLF Injection via AIA OCSP URL Path
New
3.7
CVSS
0.1%
EPSS
No
On KEV
Description
LibreSSL ocspcheck through 4.4.0 contains a CRLF injection vulnerability that allows attackers to inject HTTP headers by embedding CR/LF sequences in a certificate's AIA OCSP URI path. Because url2host() copies the path without rejecting control characters and http_open() places it in the POST request line, attackers can inject headers or split OCSP requests sent to the responder host.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 4% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
LibreSSL · OpenBSD
through 4.4.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-118372
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-118372
patch
https://github.com/openbsd/src/commit/6efdc4cce3fac9fa7208a9452f84de34c5a68e9f
patch
https://github.com/openbsd/src/commit/3adb7688a5bcfb675fa6d8b10e242022d620a23d
technical-description
https://github.com/openbsd/src/blob/17a8e44328ee2505d69723a126a390a526e50370/usr.sbin/ocspcheck/http.c#L344
technical-description
https://github.com/openbsd/src/blob/17a8e44328ee2505d69723a126a390a526e50370/usr.sbin/ocspcheck/ocspcheck.c#L154
release-notes
https://ftp.openbsd.org/pub/OpenBSD/LibreSSL/libressl-4.4.0-relnotes.txt
product
https://github.com/libressl/portable
More from LibreSSL
9.8
CVE-2023-35784
A double free or use after free could occur after SSL_clear in OpenBSD 7.2 before errata 026 and 7.3 before errata 004, and in LibreSSL before 3.6.3 and 3.7.x before 3.7.3
9.8
CVE-2021-46880
x509/x509_verify.c in LibreSSL before 3.4.2, and OpenBSD before 7.0 errata 006, allows authentication bypass because an error for an unverified certificate chain is sometimes…
9.8
CVE-2015-5334
Off-by-one error in the OBJ_obj2txt function in LibreSSL before 2.3.1 allows remote attackers to cause a denial of service (program crash) or possible execute arbitrary code via a…
7.5
CVE-2015-5333
Memory leak in the OBJ_obj2txt function in LibreSSL before 2.3.1 allows remote attackers to cause a denial of service (memory consumption) via a large number of ASN.1 object…
7.4
CVE-2018-8970
The int_x509_param_set_hosts function in lib/libcrypto/x509/x509_vpm.c in LibreSSL 2.7.0 before 2.7.1 does not support a certain special case of a zero name length, which causes…