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Fencer Vulns
high 7.5

CVE-2026-55967 json

AES-GCM streaming APIs do not reject >64 GiB cumulative single messages, enabling counter wrap and keystream reuse

published 2026-06-25 4 mo ago modified 2026-10-24 16 d ago also EUVD-2026-39493 , GHSA-q4q5-jx42-4xp9 , JLSEC-2026-739

cvss
7.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 7%
public exploits
0
none known

Summary

AES-GCM encryption/decryption with extremely large cumulative single message sizes (>64 GiB) were not properly rejected by the streaming APIs, allowing counter wrap, keystream reuse, and consequent plaintext recovery.

Patch / fix

  • julia wolfSSL_jll 5.9.2+0
  • wolfssl wolfssl 5.9.2
  • wolfssl Debian 12 5.5.4-2+deb12u3
  • wolfssl Debian 13 5.7.2-0.1+deb13u2

debian advisories DEBIAN-CVE-2026-55967

  • wolfssl Alpine 3.24 5.9.2-r0

alpine advisories ALPINE-CVE-2026-55967

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
4 mo ago

Exploit prediction

0.18% chance of exploitation in the next 30 days, higher than 7% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 4.0 2.0 CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
CNA 4.0 2.0 CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
OSV 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Affected packages

ecosystem package affected fixed in
julia wolfSSL_jll
<5.9.2+0
5.9.2+0

Affected products

  • wolfSSL wolfSSL

Classification

Weakness
  • CWE-323 Reusing a Nonce, Key Pair in Encryption

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.