CVE-2023-25135
vBulletin before 5.6.9 PL1 allows an unauthenticated remote attacker to execute arbitrary code via a crafted HTTP request that triggers deserialization.
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 23.9%, higher than 98% of all known CVEs. Patch or mitigate before the next change window.
Description
vBulletin before 5.6.9 PL1 allows an unauthenticated remote attacker to execute arbitrary code via a crafted HTTP request that triggers deserialization. This occurs because verify_serialized checks that a value is serialized by calling unserialize and then checking for errors. The fixed versions are 5.6.7 PL1, 5.6.8 PL1, and 5.6.9 PL1.
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 23.93% probability · 98th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-502
- Affected
- vbulletin/vbulletin
- Source
- cve@mitre.org
EPSS 23.9% since 3 November 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://forum.vbulletin.com/forum/vbulletin-announcements/vbulletin-announcements_aa/4473890-vbulletin-5-6-9-security-patchRelease Notes, Vendor Advisory
- https://www.ambionics.io/blog/vbulletin-unserializable-but-unreachableExploit, Technical Description, Third Party Advisory
- https://forum.vbulletin.com/forum/vbulletin-announcements/vbulletin-announcements_aa/4473890-vbulletin-5-6-9-security-patchRelease Notes, Vendor Advisory
- https://www.ambionics.io/blog/vbulletin-unserializable-but-unreachableExploit, Technical Description, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.