CVE-2026-55967

Description

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.

CVSS v3.1 Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS — Exploit Prediction

0.0011

Probability of exploitation

0.02%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-323 CWE-323

Affected Products

Vendor	Product	Versions
wolfssl	wolfssl	4.8.0 — 5.9.2

References

Advisories & Patches

https://github.com/wolfSSL/wolfssl/pull/10709 https://www.wolfssl.com/docs/security-vulnerabilities/

Frequently Asked Questions

What is CVE-2026-55967? +

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. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2026-55967? +

CVE-2026-55967 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0011, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-55967? +

CVE-2026-55967 affects products from wolfssl, specifically: wolfssl. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-55967? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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