CVE-2026-81700: openssl encrypt Signature Bypass — Fix

Description

openssl_encrypt versions before 1.4.9 contain a signature verification vulnerability in gpg_runner.verify_detached that accepts revoked and expired keys by only checking VALIDSIG status without inspecting REVKEYSIG, EXPKEYSIG, or gpg exit codes. Attackers holding compromised-then-revoked signing keys or expired project keys can bypass signature verification to execute malicious plugins in the host process.

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CVSS v3.1 Score

9.8

CRITICAL

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

EPSS — Exploit Prediction

0.0024

Probability of exploitation

0.15%

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-347 CWE-347

Affected Products

Vendor	Product	Versions
jahlives	openssl_encrypt	< 1.4.9

References

Advisories & Patches

https://github.com/jahlives/openssl_encrypt/security/advisories/GHSA-x38r-8wf3-q9hq

Other References

https://www.vulncheck.com/advisories/openssl-encrypt-before-1.4.9-gpg-signature-verification-bypass

Frequently Asked Questions

What is CVE-2026-81700? +

openssl_encrypt versions before 1.4.9 contain a signature verification vulnerability in gpg_runner.verify_detached that accepts revoked and expired keys by only checking VALIDSIG status without inspecting REVKEYSIG, EXPKEYSIG, or gpg exit codes. Attackers holding compromised-then-revoked signing keys or expired project keys can bypass signature verification to execute malicious plugins in the host process. It has a CVSS v3.1 base score of 9.8 (CRITICAL).

How severe is CVE-2026-81700? +

CVE-2026-81700 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately. The EPSS score is 0.0024, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-81700? +

CVE-2026-81700 affects products from jahlives, specifically: openssl_encrypt. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-81700? +

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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