CVE-2024-27354: phpseclib DoS (CVSS 7.5)

Description

An issue was discovered in phpseclib 1.x before 1.0.23, 2.x before 2.0.47, and 3.x before 3.0.36. An attacker can construct a malformed certificate containing an extremely large prime to cause a denial of service (CPU consumption for an isPrime primality check). NOTE: this issue was introduced when attempting to fix CVE-2023-27560.

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CVSS v3.1 Score

7.5

HIGH

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

Weakness Type (CWE)

CWE-400 Uncontrolled Resource Consumption

Affected Products

Vendor	Product	Versions
phpseclib	phpseclib	1.0.0 — 1.0.23
phpseclib	phpseclib	2.0.0 — 2.0.47
phpseclib	phpseclib	3.0.0 — 3.0.36
debian	debian_linux	All

References

Other References

https://gist.github.com/katzj/ee72f3c2a00590812b2ea3c0c8890e0b https://github.com/phpseclib/phpseclib/blob/master/phpseclib/Math/PrimeField.php#L49 https://lists.debian.org/debian-lts-announce/2024/03/msg00002.html https://lists.debian.org/debian-lts-announce/2024/03/msg00003.html https://gist.github.com/katzj/ee72f3c2a00590812b2ea3c0c8890e0b https://github.com/phpseclib/phpseclib/blob/master/phpseclib/Math/PrimeField.php#L49 https://lists.debian.org/debian-lts-announce/2024/03/msg00002.html https://lists.debian.org/debian-lts-announce/2024/03/msg00003.html

Frequently Asked Questions

What is CVE-2024-27354? +

An issue was discovered in phpseclib 1.x before 1.0.23, 2.x before 2.0.47, and 3.x before 3.0.36. An attacker can construct a malformed certificate containing an extremely large prime to cause a denial of service (CPU consumption for an isPrime primality check). NOTE: this issue was introduced when attempting to fix CVE-2023-27560. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2024-27354? +

CVE-2024-27354 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.

What products are affected by CVE-2024-27354? +

CVE-2024-27354 affects products from debian, phpseclib, specifically: debian_linux, phpseclib. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-27354? +

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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