CVE-2023-49316: High severity phpseclib phpseclib vulnerability

Published Nov 27, 2023
·
Updated

Impact Anyone loading untrusted ASN1 files (eg. X509 certificates, RSA PKCS8 private or public keys, etc)

Patches https://github.com/phpseclib/phpseclib/commit/964d78101a70305df33f442f5490f0adb3b7e77f

Workarounds No.

References https://github.com/phpseclib/phpseclib/commit/964d78101a70305df33f442f5490f0adb3b7e77f https://www.usenix.org/system/files/usenixsecurity25-shi-bing.pdf

Other sources

In Math/BinaryField.php in phpseclib 3 before 3.0.34, excessively large degrees can lead to a denial of service.

MITRE

In Math/BinaryField.php in phpseclib 3 before 3.0.34, excessively large degrees in binary fields can lead to a denial of service.

Affected Software

2 affected componentsFixes available
composer/phpseclib/phpseclib>=3.0.0<3.0.34
3.0.34
phpseclib phpseclib>=3.0.0<3.0.34

Event History

Nov 27, 2023
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
Description
Data Sourced
via NVD·06:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
Advisory Published
06:31 PM
May 8, 2026
Advisory Published
via GitHub·11:06 PM
Data Sourced
via GitHub·11:06 PM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is CVE-2023-49316?

CVE-2023-49316 is a vulnerability in phpseclib before version 3.0.34 that allows for a denial of service attack due to excessively large degrees in binary fields.

2

How does CVE-2023-49316 affect phpseclib?

CVE-2023-49316 affects phpseclib versions prior to 3.0.34.

3

How can CVE-2023-49316 be exploited?

CVE-2023-49316 can be exploited by sending inputs with excessively large degrees in binary fields, leading to a denial of service.

4

What is the fix for CVE-2023-49316?

The fix for CVE-2023-49316 is to update phpseclib to version 3.0.34 or later.

5

Where can I find more information about CVE-2023-49316?

More information about CVE-2023-49316 can be found at the following references: [GitHub commit](https://github.com/phpseclib/phpseclib/commit/964d78101a70305df33f442f5490f0adb3b7e77f), [GitHub release](https://github.com/phpseclib/phpseclib/releases/tag/3.0.34), [NVD](https://nvd.nist.gov/vuln/detail/CVE-2023-49316)

Contact

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