How severe is CVE-2024-27355?

CVE-2024-27355 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2024-27355 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-27355?

CVE-2024-27355 primarily affects Phpseclib. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2024-27355?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2024-27355 have an EU (EUVD) identifier?

Yes. CVE-2024-27355 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-0951.

When was CVE-2024-27355 published?

CVE-2024-27355 was published on 2024-03-01 and last updated on 2026-06-17.

CVE-2024-27355

CVE-2024-27355 is a high-severity vulnerability in Phpseclib with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-400.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (43rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-0951
Weakness: CWE-400
Affected product: Phpseclib
Published: 2024-03-01
Last modified: 2026-06-17

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. When processing the ASN.1 object identifier of a certificate, a sub identifier may be provided that leads to a denial of service (CPU consumption for decodeOID).

Frequently asked questions

What is CVE-2024-27355?: 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. When processing the ASN.1 object identifier of a certificate, a sub identifier may be provided that leads to a denial of service (CPU consumption for decodeOID).
How severe is CVE-2024-27355?: CVE-2024-27355 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2024-27355 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-27355?: CVE-2024-27355 primarily affects Phpseclib. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2024-27355?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2024-27355 have an EU (EUVD) identifier?: Yes. CVE-2024-27355 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-0951.
When was CVE-2024-27355 published?: CVE-2024-27355 was published on 2024-03-01 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:phpseclib:phpseclib:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

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