Vulnerability · CVE-2026-61511
vBulletin vBulletin Improper Neutralization of Directives in Dynamically Evaluated Code ('Eval Injection')
Published Jul 27, 2026 · catalog updated Oct 14, 2026 · vBulletin vBulletin
Patch now
CVE-2026-61511 is in the CISA known-exploited catalog. Confirm vBulletin vBulletin against the vendor advisory and apply that fix. The CVSS score does not change the priority.
Gaps on this record
- No version range is stored. A customer cannot check an installed version against this record.
- Severity
- Critical9.3
- Known exploitation
- CISA KEV and VulnCheck KEV
- EPSS
- 5.61%
- Remediation
- Remediation guidance
- Affected products
- vendor vBulletin vBulletin
vBulletin 5.x through 5.7.5 and 6.x through 6.2.1 contains an eval injection vulnerability in the vB5_Template_Runtime::runMaths() method within the template runtime that allows unauthenticated remote attackers to execute arbitrary PHP code by supplying crafted input through the pagenav[pagenumber] parameter. Attackers can exploit the insufficiently restrictive regex filter by using phpfuck-style encoding with permitted characters to inject and execute arbitrary PHP code via the unauthenticated ajax/render template route without any authentication. VulnCheck canary evidence. Initial-access exploit intelligence.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- vendor vBulletin vBulletinversion unspecified
How to fix CVE-2026-61511
Recommended remediation
Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
CVE-2026-61511 is in the CISA known-exploited catalog. Confirm vBulletin vBulletin against the vendor advisory and apply that fix. The CVSS score does not change the priority.
Which versions are affected?
Affected version ranges are not on this record. Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
What should an analyst verify?
CWE-95. EPSS 5.61%. The CISA KEV listing is the exploitation evidence. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Jul 27, 2026 · NIST NVD
Detected
vBulletin 5.x through 5.7.5 and 6.x through 6.2.1 contains an eval injection vulnerability in the vB5_Template_Runtime::runMaths() method within the template runtime that allows unauthenticated remote attackers to execute arbitrary PHP code by supplying crafted input through the pagenav[pagenumber] parameter. Attackers can exploit the insufficiently restrictive regex filter by using phpfuck-style
Aug 27, 2026 · CISA KEV
Known exploited
Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Oct 14, 2026 · NIST NVD
Updated
vBulletin 5.x through 5.7.5 and 6.x through 6.2.1 contains an eval injection vulnerability in the vB5_Template_Runtime::runMaths() method within the template runtime that allows unauthenticated remote attackers to execute arbitrary PHP code by supplying crafted input through the pagenav[pagenumber] parameter. Attackers can exploit the insufficiently restrictive regex filter by using phpfuck-style
Sources
- CVE.orgVulnerability recordCVE-2026-61511
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-61511
30-day exploitation probability 5.6%
first.org - NIST NVDVulnerability recordCVE-2026-61511
vBulletin 5.x through 5.7.5 and 6.x through 6.2.1 contains an eval injection vulnerability in the vB5_Template_Runtime::runMaths() method within the template runtime that allows unauthenticated remote attackers to execute arbitrary PHP code by supplying crafted input through the
nvd.nist.gov - VulnCheck KEVConfirmed exploitationCVE-2026-61511
vBulletin 5.x through 5.7.5 and 6.x through 6.2.1 contains an eval injection vulnerability in the vB5_Template_Runtime::runMaths() method within the template runtime that allows unauthenticated remote attackers to execute arbitrary PHP code by supplying crafted input through the
vulncheck.com
References
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.