CVE catalog
CVE-2026-88052
Tesseract is an open source OCR engine. In version 5.5.3 and earlier, UNICHARSET::load_via_fgets in src/ccutil/unicharset.cpp trusts the declared unichar count as a loop bound and uses id as an unchec
- Severity
- High · CVSS 8.6
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/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 - Published
- Updated
- Source
- [NVD] · [CVE record]
- EPSS
- 0.18% · Oct 25, 2026
Tesseract is an open source OCR engine. In version 5.5.3 and earlier, UNICHARSET::load_via_fgets in src/ccutil/unicharset.cpp trusts the declared unichar count as a loop bound and uses id as an unchecked index into the unichars vector. unichar_insert_backwards_compatible can leave the vector unchanged for an empty, duplicate, or already-encodable representation, causing id to become larger than unichars.size(). Subsequent set_* calls and the write to unichars[id].properties.enabled then write UNICHAR_PROPERTIES beyond the vector during initialization in both the default LSTM and legacy engines, causing heap corruption, a crash, or potentially controlled corruption. No fixed release is available as of this review.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | tesseract | sid | 5.5.0-1.1 | vulnerable |
| Debian | tesseract | forky | 5.5.0-1.1 | vulnerable |
| Debian | tesseract | trixie | 5.5.0-1 | vulnerable |
| Debian | tesseract | bookworm | 5.3.0-2 | vulnerable |
| Cpe | tesseract_ocr | Not reported | Not reported | unknown |
| Ubuntu | tesseract | noble | 5.3.4-1ubuntu0.1~esm1 | fixed |
| Ubuntu | libtesseract-dev | noble | 5.3.4-1ubuntu0.1~esm1 | fixed |
| Ubuntu | libtesseract5 | noble | 5.3.4-1ubuntu0.1~esm1 | fixed |
| Ubuntu | tesseract-ocr | noble | 5.3.4-1ubuntu0.1~esm1 | fixed |
| Ubuntu | tesseract-ocr-all | noble | 5.3.4-1ubuntu0.1~esm1 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | tesseract | source | sid | (unfixed) | not yet assigned | Not reported | [1147403] |
| Debian | tesseract | source | forky | (unfixed) | not yet assigned | Not reported | [1147403] |
| Debian | tesseract | source | trixie | (unfixed) | not yet assigned | Not reported | [1147403] |
| Debian | tesseract | source | bookworm | (unfixed) | not yet assigned | Not reported | [1147403] |
| Ubuntu | tesseract | deb | noble | 5.3.4-1ubuntu0.1~esm1 | Not reported | Not reported | Not reported |
| Ubuntu | libtesseract-dev | deb | noble | 5.3.4-1ubuntu0.1~esm1 | Not reported | Not reported | Not reported |
| Ubuntu | libtesseract5 | deb | noble | 5.3.4-1ubuntu0.1~esm1 | Not reported | Not reported | Not reported |
| Ubuntu | tesseract-ocr | deb | noble | 5.3.4-1ubuntu0.1~esm1 | Not reported | Not reported | Not reported |
| Ubuntu | tesseract-ocr-all | deb | noble | 5.3.4-1ubuntu0.1~esm1 | Not reported | Not reported | Not reported |
Notes
[trixie] tesseract: Minor issue
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [libtesseract5]Affected
Source package: [tesseract]
Details (2)
5.3.0-2· amd64 · bookwormAffected
nvd · tesseract · debian · bookworm; nvd · tesseract · debian · 12
5.3.0-2· arm64 · bookwormAffected
nvd · tesseract · debian · bookworm; nvd · tesseract · debian · 12
- [libtesseract-dev]Affected
Source package: [tesseract]
Details (2)
5.3.0-2· amd64 · bookwormAffected
nvd · tesseract · debian · bookworm; nvd · tesseract · debian · 12
5.3.0-2· arm64 · bookwormAffected
nvd · tesseract · debian · bookworm; nvd · tesseract · debian · 12
- [tesseract-ocr]Affected
Source package: [tesseract]
Details (2)
5.3.0-2· amd64 · bookwormAffected
nvd · tesseract · debian · bookworm; nvd · tesseract · debian · 12
5.3.0-2· arm64 · bookwormAffected
nvd · tesseract · debian · bookworm; nvd · tesseract · debian · 12
- [tesseract-ocr-all]Affected
Source package: [tesseract]
Details (2)
5.3.0-2· all · bookwormAffected
nvd · tesseract · debian · bookworm; nvd · tesseract · debian · 12
5.3.0-2· all · bookwormAffected
nvd · tesseract · debian · bookworm; nvd · tesseract · debian · 12
[Debian 13 (Trixie)]
- [libtesseract5]Affected
Source package: [tesseract]
Details (2)
5.5.0-1+b1· amd64 · trixieAffected
nvd · tesseract · debian · 13
5.5.0-1+b1· arm64 · trixieAffected
nvd · tesseract · debian · 13
- [libtesseract-dev]Affected
Source package: [tesseract]
Details (2)
5.5.0-1+b1· amd64 · trixieAffected
nvd · tesseract · debian · 13
5.5.0-1+b1· arm64 · trixieAffected
nvd · tesseract · debian · 13
- [tesseract-ocr]Affected
Source package: [tesseract]
Details (2)
5.5.0-1+b1· amd64 · trixieAffected
nvd · tesseract · debian · 13
5.5.0-1+b1· arm64 · trixieAffected
nvd · tesseract · debian · 13
- [tesseract-ocr-all]Affected
Source package: [tesseract]
Details (2)
5.5.0-1· all · trixieAffected
nvd · tesseract · debian · 13
5.5.0-1· all · trixieAffected
nvd · tesseract · debian · 13
Observed:
References
- [https://ftp.suse.com/pub/projects/security/csaf/opensuse-su-2026_11887-1.json]
- [https://nvd.nist.gov/vuln/detail/CVE-2026-88052]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-88052]
- [https://security-tracker.debian.org/tracker/CVE-2026-88052]
- [https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-88052.json]
- [https://ubuntu.com/security/notices/USN-8882-1]
[Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX] · [Ubuntu Security Notices (USN)]