Description
An issue was discovered in TCPDF before 6.8.0. unserializeTCPDFtag uses != (aka loose comparison) and does not use a constant-time function to compare TCPDF tag hashes.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| tecnick | tcpdf | < 6.8.0 | 6.8.0 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | tcpdf | 6.8.0+dfsg-1 | — |
| Debian 13 | tcpdf | 6.8.0+dfsg-1 | — |
| Debian 12 | tcpdf | 6.6.2+dfsg1-1+deb12u1 | DSA-5933-1 |
| Debian 11 | tcpdf | 6.3.5+dfsg1-1+deb11u1 | DLA-4199-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | tcpdf | No fix yet | — |
| Ubuntu 22.04 LTS | tcpdf | No fix yet | — |
| Ubuntu 20.04 LTS | tcpdf | No fix yet | — |
| Ubuntu 18.04 LTS | tcpdf | No fix yet | — |
| Ubuntu 16.04 LTS | tcpdf | No fix yet | — |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 14.04 LTS | tcpdf | No fix yet | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Packagist | tecnickcom/tcpdf | < 6.8.0 | 6.8.0 | GHSA-w95c-7994-ghpr |
Advisories 2
- DSA-5933-1 tcpdf - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-4199-1 tcpdf - security update Debian Security (DSA / DLA) · Mar 9, 2026