DEBIAN-CVE-2026-6291

Source
https://security-tracker.debian.org/tracker/CVE-2026-6291
Import Source
https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-6291.json
JSON Data
https://api.osv.dev/v1/vulns/DEBIAN-CVE-2026-6291
Upstream
Published
2026-06-25T18:16:41Z
Modified
2026-09-14T17:03:11Z
Severity
  • 6.5 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N CVSS Calculator
Summary
[none]
Details

Bleichenbacher padding oracle in PKCS#7 KTRI decryption. When decrypting PKCS#7 EnvelopedData using RSA PKCS#1 v1.5 key transport, wolfSSL returned distinguishable error codes depending on whether RSA padding validation failed versus whether the decrypted content was malformed. An attacker able to submit crafted EnvelopedData messages and observe error responses could use this as a padding oracle to incrementally recover the encrypted Content Encryption Key (CEK). The fix generates a deterministic pseudo-random fake CEK on padding failure (via HMAC-SHA256) and proceeds with decryption identically, using constant-time operations throughout, so that all failure paths produce the same error regardless of padding validity.

References

Affected packages

Debian:12 / wolfssl

Package

Name
wolfssl
Purl
pkg:deb/debian/wolfssl?arch=source&distro=bookworm

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

5.*
5.5.4-2
5.5.4-2+deb12u1
5.5.4-2+deb12u2
5.5.4-2+deb12u3
5.5.4-2.1
5.6.4-1
5.6.4-2
5.6.6-1
5.6.6-1.1
5.6.6-1.2
5.6.6-1.3~exp1
5.6.6-1.3
5.7.0-0.1
5.7.0-0.2
5.7.0-0.3
5.7.2-0.1
5.7.2-0.2
5.7.2-0.3
5.7.2-0.4
5.8.2-1
5.8.2-1.1
5.8.2-1.2
5.8.4-1
5.9.0-0.1
5.9.0-0.2
5.9.1-0.1
5.9.2-1

Ecosystem specific

{
    "urgency":  "end-of-life"
}

Database specific

source
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-6291.json"

Debian:13 / wolfssl

Package

Name
wolfssl
Purl
pkg:deb/debian/wolfssl?arch=source&distro=trixie

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

5.*
5.7.2-0.1
5.7.2-0.1+deb13u1
5.7.2-0.1+deb13u2
5.7.2-0.2
5.7.2-0.3
5.7.2-0.4
5.8.2-1
5.8.2-1.1
5.8.2-1.2
5.8.4-1
5.9.0-0.1
5.9.0-0.2
5.9.1-0.1
5.9.2-1

Ecosystem specific

{
    "urgency":  "not yet assigned"
}

Database specific

source
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-6291.json"