CVE-2024-27354

highpriority · track · 0EPSS 0.006 · 49 %ileEUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.60% (49th) EPSS
CVSS 7.5 · high
Is it mine?
10 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · nvd · osv

EPSS · scored 2026-10-28

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.

01

cvss

Technical severity, 0–10. One row per scoring source.

7.5
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–7.5

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondaryexploitability 3.9 · impact 3.6
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · OSV
v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-400USCWE-400US
04

affected products (10)

Products and version ranges known to be affected.

05

advisories (2)

Vendor and ecosystem advisories describing this.

  • GHSA-2528-jw5q-ww88phpseclib: guardrails needed on isPrime and randomPrime2026-05-06ghsa · osvUS

    ### Impact Anyone trying to generate a prime and testing the primality of a number. ### Patches https://github.com/phpseclib/phpseclib/commit/ad5dbdf2129f5e0fb644637770b7f33de8ca8575 ### Workarounds Using the GMP extension would probably help, assuming that one has its own guardrails. ### Resources https://github.com/phpseclib/phpseclib/commit/ad5dbdf2129f5e0fb644637770b7f33de8ca8575 https://www.usenix.org/system/files/conference/usenixsecurity25/sec25cycle1-prepub-599-shi-bing.pdf

  • GHSA-hg35-mp25-qf6hDuplicate Advisory: phpseclib: guardrails needed on isPrime and randomPrime2024-03-02ghsa · osvUS

    ### Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-2528-jw5q-ww88. This link is maintained to preserve external references. ### Original 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.

06

also known as (4)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

cnnvdenisa_euvdnvdosvNVDCVE.orgMITRE
published 2024-03-01modified 2026-06-17
08

references (19)

External citations — patches, advisories, analysis.

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