How severe is CVE-2023-27560?

CVE-2023-27560 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-2023-27560 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-27560?

CVE-2023-27560 affects Phpseclib. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-27560?

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.

When was CVE-2023-27560 published?

CVE-2023-27560 was published on 2023-03-03 and last updated on 2026-06-17.

CVE-2023-27560

CVE-2023-27560 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-835.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (53rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-835
Affected product: Phpseclib
Published: 2023-03-03
Last modified: 2026-06-17

Description

Math/PrimeField.php in phpseclib 3.x before 3.0.19 has an infinite loop with composite primefields.

Frequently asked questions

What is CVE-2023-27560?: Math/PrimeField.php in phpseclib 3.x before 3.0.19 has an infinite loop with composite primefields.
How severe is CVE-2023-27560?: CVE-2023-27560 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-2023-27560 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-27560?: CVE-2023-27560 affects Phpseclib. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-27560?: 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.
When was CVE-2023-27560 published?: CVE-2023-27560 was published on 2023-03-03 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:phpseclib:phpseclib:*:*:*:*:*:*:*:*

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