phpseclib Infinite Loop vulnerability

Description

Math/PrimeField.php in phpseclib has an infinite loop with composite primefields. This vulnerability was introduced in version 3.0.0, and has been patched in 3.0.19. The CVE for this issue originally identified the the vulnerable version as 2.x, however, the vulnerable functionality was not introduced until version 3.

Basic information

Type
reviewed
Severity
high
Advisory on GitHub
Open advisory ↗
Repository advisory
Source code
Browse source ↗
Published (advisory)
2023-03-03 06:30:17 UTC
Updated
2025-03-06 21:36:14 UTC
GitHub reviewed
2023-03-03 23:01:05 UTC
NVD published
2023-03-03

EPSS Score

Score Percentile
0.27% 50.20%

CVSS Scores

Base score Version Severity Vector
7.5 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.

Identifiers

CWEs

CWE id Name
CWE-835 Loop with Unreachable Exit Condition ('Infinite Loop')

Credits

  • janedbal (analyst)

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
composer phpseclib/phpseclib >= 3.0.0, < 3.0.19 3.0.19

References

cvelogic Threat Intelligence