Broken Access Control in extension "Telephone Directory" (telephonedirectory)

published 2026-08-25 2 mo ago modified 2026-09-28 41 d ago also EUVD-2026-65336

cvss: 8.7; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 35%
public exploits: 0; none known

The extension validates the HMAC of a frontend employee edit link only in the action that renders the edit form, not in the action that persists the change. An unauthenticated visitor who knows the UID of a visible employee record can send a direct POST request to the update action and overwrite that record without a valid edit link or any ownership check.

Patch / fix

fixed in 1

TYPO3 Extension "Telephone Directory" 4.1.1, 5.0.1, 6.2.0

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 2 mo ago (2026-08-25)

Exploit prediction

0.41% chance of exploitation in the next 30 days, higher than 35% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	4.0	8.7	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
CNA	4.0	8.7	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

TYPO3 Extension "Telephone Directory"

Classification

Weakness

CWE-862 Missing Authorization
CWE-639 Authorization Bypass Through User-Controlled Key

References

typo3.org /security/advisory/typo3-ext-sa-2026-018
vendor-advisory

Sources

CVE List CVE-2026-77140
NVD CVE-2026-77140

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary