CVE-Katalog

CVE-2025-66199

OpenSSL vulnerabilities

Schweregrad: Medium · CVSS 5.9CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Published: Jan 27, 2026, 4:16:15 PM UTC
Source: [NVD] · [CVE record]
EPSS: 0.45% · Oct 22, 2026

Issue summary: A TLS 1.3 connection using certificate compression can be forced to allocate a large buffer before decompression without checking against the configured certificate size limit. Impact summary: An attacker can cause per-connection memory allocations of up to approximately 22 MiB and extra CPU work, potentially leading to service degradation or resource exhaustion (Denial of Service). In affected configurations, the peer-supplied uncompressed certificate length from a CompressedCertificate message is used to grow a heap buffer prior to decompression. This length is not bounded by the max_cert_list setting, which otherwise constrains certificate message sizes. An attacker can exploit this to cause large per-connection allocations followed by handshake failure. No memory corruption or information disclosure occurs. This issue only affects builds where TLS 1.3 certificate compression is compiled in (i.e., not OPENSSL_NO_COMP_ALG) and at least one compression algorithm (brotli, zlib, or zstd) is available, and where the compression extension is negotiated. Both clients receiving a server CompressedCertificate and servers in mutual TLS scenarios receiving a client CompressedCertificate are affected. Servers that do not request client certificates are not vulnerable to client-initiated attacks. Users can mitigate this issue by setting SSL_OP_NO_RX_CERTIFICATE_COMPRESSION to disable receiving compressed certificates. The FIPS modules in 3.6, 3.5, 3.4 and 3.3 are not affected by this issue, as the TLS implementation is outside the OpenSSL FIPS module boundary. OpenSSL 3.6, 3.5, 3.4 and 3.3 are vulnerable to this issue. OpenSSL 3.0, 1.1.1 and 1.0.2 are not affected by this issue.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

Distribution	Package	Release	Version	Status
Debian	openssl	sid	`3.6.5-1`	fixed
Debian	openssl	forky	`3.6.5-1`	fixed
Debian	openssl	trixie	`3.5.7-1~deb13u2`	fixed
Debian	openssl	trixie-security	`3.5.7-1~deb13u3`	fixed
Debian	openssl	bookworm	`3.0.20-1~deb12u2`	not affected
Debian	openssl	bookworm-security	`3.0.22-1~deb12u1`	not affected
Ubuntu	openssl	noble	Not reported	not affected
Ubuntu	openssl	noble	`3.0.13-0ubuntu3.7`	fixed
Ubuntu	libssl-dev	noble	`3.0.13-0ubuntu3.7`	fixed
Ubuntu	libssl-doc	noble	`3.0.13-0ubuntu3.7`	fixed
Ubuntu	libssl3t64	noble	`3.0.13-0ubuntu3.7`	fixed
Alpine	openssl	3.20	`3.3.6-r0`	fixed
Alpine	openssl	3.21	`3.3.6-r0`	fixed
Alpine	openssl	3.22	`3.5.5-r0`	fixed
Alpine	openssl	3.23	`3.5.5-r0`	fixed
Alpine	openssl	3.24	`3.5.5-r0`	fixed

Fixed-version evidence

Distribution	Package	Type	Release	Fixed version	Urgency	Origin	Bugs
Debian	openssl	source	sid	`3.5.5-1`	not yet assigned	Not reported	Not reported
Debian	openssl	source	forky	`3.5.5-1`	not yet assigned	Not reported	Not reported
Debian	openssl	source	trixie	`3.5.4-1~deb13u2`	not yet assigned	Not reported	Not reported
Debian	openssl	source	bookworm	`Not affected`	unimportant	Not reported	Not reported
Ubuntu	openssl	deb	noble	`3.0.13-0ubuntu3.7`	Not reported	Not reported	Not reported
Ubuntu	libssl-dev	deb	noble	`3.0.13-0ubuntu3.7`	Not reported	Not reported	Not reported
Ubuntu	libssl-doc	deb	noble	`3.0.13-0ubuntu3.7`	Not reported	Not reported	Not reported
Ubuntu	libssl3t64	deb	noble	`3.0.13-0ubuntu3.7`	Not reported	Not reported	Not reported
Alpine	openssl	apk	3.20	`3.3.6-r0`	Not reported	ALPINE-CVE-2025-66199	Not reported
Alpine	openssl	apk	3.21	`3.3.6-r0`	Not reported	ALPINE-CVE-2025-66199	Not reported
Alpine	openssl	apk	3.22	`3.5.5-r0`	Not reported	ALPINE-CVE-2025-66199	Not reported
Alpine	openssl	apk	3.23	`3.5.5-r0`	Not reported	ALPINE-CVE-2025-66199	Not reported
Alpine	openssl	apk	3.24	`3.5.5-r0`	Not reported	ALPINE-CVE-2025-66199	Not reported

OpenFactory catalog packages

Die Paketzuordnung läuft.

[Debian 12 (Bookworm)]

[libssl3]Unbekannt
Quellpaket: [openssl]
Details (6)
- 3.0.20-1~deb12u2 · amd64 · bookworm
  Nicht betroffen
  usn · openssl · debian · bookworm
- 3.0.20-1~deb12u2 · arm64 · bookworm
  Nicht betroffen
  usn · openssl · debian · bookworm
- 3.0.20-1~deb12u2 · amd64 · bookworm-security
  Nicht betroffen
  usn · openssl · debian · bookworm
- 3.0.20-1~deb12u2 · arm64 · bookworm-security
  Nicht betroffen
  usn · openssl · debian · bookworm
- 3.0.17-1~deb12u2 · amd64 · bookworm-updates
  Nicht betroffen
  usn · openssl · debian · bookworm
- 3.0.17-1~deb12u2 · arm64 · bookworm-updates
  Nicht betroffen
  usn · openssl · debian · bookworm
[libssl-dev]Unbekannt
Quellpaket: [openssl]
Details (6)
- 3.0.20-1~deb12u2 · amd64 · bookworm
  Nicht betroffen
  usn · openssl · debian · bookworm
- 3.0.20-1~deb12u2 · arm64 · bookworm
  Nicht betroffen
  usn · openssl · debian · bookworm
- 3.0.20-1~deb12u2 · amd64 · bookworm-security
  Nicht betroffen
  usn · openssl · debian · bookworm
- 3.0.20-1~deb12u2 · arm64 · bookworm-security
  Nicht betroffen
  usn · openssl · debian · bookworm
- 3.0.17-1~deb12u2 · amd64 · bookworm-updates
  Nicht betroffen
  usn · openssl · debian · bookworm
- 3.0.17-1~deb12u2 · arm64 · bookworm-updates
  Nicht betroffen
  usn · openssl · debian · bookworm
[libssl-doc]Unbekannt
Quellpaket: [openssl]
Details (6)
- 3.0.20-1~deb12u2 · all · bookworm
  Nicht betroffen
  usn · openssl · debian · bookworm
- 3.0.20-1~deb12u2 · all · bookworm
  Nicht betroffen
  usn · openssl · debian · bookworm
- 3.0.20-1~deb12u2 · all · bookworm-security
  Nicht betroffen
  usn · openssl · debian · bookworm
- 3.0.20-1~deb12u2 · all · bookworm-security
  Nicht betroffen
  usn · openssl · debian · bookworm
- 3.0.17-1~deb12u2 · all · bookworm-updates
  Nicht betroffen
  usn · openssl · debian · bookworm
- 3.0.17-1~deb12u2 · all · bookworm-updates
  Nicht betroffen
  usn · openssl · debian · bookworm
[openssl]Unbekannt
Details (6)
- 3.0.20-1~deb12u2 · amd64 · bookworm
  Nicht betroffen
  usn · openssl · debian · bookworm
- 3.0.20-1~deb12u2 · arm64 · bookworm
  Nicht betroffen
  usn · openssl · debian · bookworm
- 3.0.20-1~deb12u2 · amd64 · bookworm-security
  Nicht betroffen
  usn · openssl · debian · bookworm
- 3.0.20-1~deb12u2 · arm64 · bookworm-security
  Nicht betroffen
  usn · openssl · debian · bookworm
- 3.0.17-1~deb12u2 · amd64 · bookworm-updates
  Nicht betroffen
  usn · openssl · debian · bookworm
- 3.0.17-1~deb12u2 · arm64 · bookworm-updates
  Nicht betroffen
  usn · openssl · debian · bookworm

[Debian 13 (Trixie)]

[libssl3t64]Unbekannt
Quellpaket: [openssl]
Details (6)
- 3.5.6-1~deb13u2 · amd64 · trixie
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.6-1~deb13u2 · arm64 · trixie
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.6-1~deb13u2 · amd64 · trixie-security · Historical version
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.7-1~deb13u2 · amd64 · trixie-security · Historical version
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.7-1~deb13u2 · arm64 · trixie-security
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.7-1~deb13u3 · amd64 · trixie-security
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
[libssl-dev]Unbekannt
Quellpaket: [openssl]
Details (6)
- 3.5.6-1~deb13u2 · amd64 · trixie
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.6-1~deb13u2 · arm64 · trixie
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.6-1~deb13u2 · amd64 · trixie-security · Historical version
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.7-1~deb13u2 · amd64 · trixie-security · Historical version
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.7-1~deb13u2 · arm64 · trixie-security
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.7-1~deb13u3 · amd64 · trixie-security
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
[libssl-doc]Unbekannt
Quellpaket: [openssl]
Details (6)
- 3.5.6-1~deb13u2 · all · trixie
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.6-1~deb13u2 · all · trixie
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.6-1~deb13u2 · all · trixie-security · Historical version
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.7-1~deb13u2 · all · trixie-security
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.7-1~deb13u2 · all · trixie-security · Historical version
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.7-1~deb13u3 · all · trixie-security
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
[openssl]Unbekannt
Details (6)
- 3.5.6-1~deb13u2 · amd64 · trixie
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.6-1~deb13u2 · arm64 · trixie
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.6-1~deb13u2 · amd64 · trixie-security · Historical version
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.7-1~deb13u2 · amd64 · trixie-security · Historical version
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.7-1~deb13u2 · arm64 · trixie-security
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.7-1~deb13u3 · amd64 · trixie-security
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
[openssl-provider-fips]Unbekannt
Quellpaket: [openssl]
Details (6)
- 3.5.6-1~deb13u2 · amd64 · trixie
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.6-1~deb13u2 · arm64 · trixie
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.6-1~deb13u2 · amd64 · trixie-security · Historical version
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.7-1~deb13u2 · amd64 · trixie-security · Historical version
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.7-1~deb13u2 · arm64 · trixie-security
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.7-1~deb13u3 · amd64 · trixie-security
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
[openssl-provider-legacy]Unbekannt
Quellpaket: [openssl]
Details (6)
- 3.5.6-1~deb13u2 · amd64 · trixie
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.6-1~deb13u2 · arm64 · trixie
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.6-1~deb13u2 · amd64 · trixie-security · Historical version
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.7-1~deb13u2 · amd64 · trixie-security · Historical version
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.7-1~deb13u2 · arm64 · trixie-security
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13
- 3.5.7-1~deb13u3 · amd64 · trixie-security
  Behoben · Behoben: 3.5.4-1~deb13u2
  usn · openssl · debian · 13

Beobachtet: Oct 24, 2026, 1:11:29 AM UTC

Referenzen

[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX] · [Ubuntu Security Notices (USN)]