Heap-based buffer overflow in the ParseValue function in lexer.c in tidy before 4.9.31 allows remote attackers to cause a denial of service
Heap-based buffer overflow in the ParseValue function in lexer.c in tidy before 4.9.31 allows remote attackers to cause a denial of service (crash) via vectors involving a command character in an href.
- Published
- Aug 11, 2015
- Updated
- Jun 16, 2026
- EPSS
- 4.7% · 91th percentile
- CWE
- CWE-119
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Report tools
Action score
28
Monitor
Low priority for now.
- CVSS
- 27 / 40 · 6.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 4.7%
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpAffected systems
| Vendor | Product | CPE |
|---|---|---|
| htacg | tidy | cpe:2.3:a:htacg:tidy |
| canonical | ubuntu linux | cpe:2.3:o:canonical:ubuntu_linux |
| debian | debian linux | cpe:2.3:o:debian:debian_linux |
| apple | iphone os | cpe:2.3:o:apple:iphone_os |
| apple | mac os x | cpe:2.3:o:apple:mac_os_x |
| apple | watchos | cpe:2.3:o:apple:watchos |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- apple iphone osup to 8.2 inclusive
- apple mac os xup to 10.6.8 inclusive
- apple watchosup to 1.0.1 inclusive
- canonical ubuntu linux12.04
- canonical ubuntu linux14.04
- canonical ubuntu linux15.04
- debian debian linux7.0
- debian debian linux8.0
- htacg tidyup to 4.9.30 inclusive
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:6.0 | tidy | before 20091223cvs-1+deb6u1 | 20091223cvs-1+deb6u1 |
| Debian:7 | tidy | before 20091223cvs-1.2+deb7u1 | 20091223cvs-1.2+deb7u1 |
| Debian:8 | tidy | before 20091223cvs-1.4+deb8u1 | 20091223cvs-1.4+deb8u1 |
| openSUSE:Tumbleweed | tidy | before 5.2.0-2.3 | 5.2.0-2.3 |
| SUSE:Linux Enterprise Software Development Kit 11 SP3 | tidy | before 1.0-37.1 | 1.0-37.1 |
| SUSE:Linux Enterprise Software Development Kit 12 | tidy | before 1.0.20100204cvs-25.3 | 1.0.20100204cvs-25.3 |
Same product
htacg: all recordsOther highest-scoring records for the same primary product.
- CVE-2021-33391An issue in HTACG HTML Tidy v5.7.28 allows attacker to execute arbitrary code via the -g option of the CleanNode() function in gdoc.c.39Monitor
- CVE-2017-17497In Tidy 5.7.0, the prvTidyTidyMetaCharset function in clean.c allows attackers to cause a denial of service (Segmentation Fault), because th30Monitor
- CVE-2017-13692In Tidy 5.5.31, the IsURLCodePoint function in attrs.c allows attackers to cause a denial of service (Segmentation Fault), as demonstrated b30Monitor
- CVE-2025-6498HTACG tidy-html5 alloc.c defaultAlloc memory leak7Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| debian:tidy | 20091223cvs-1+deb6u1 · Debian:6.0 | Package registry (OSV) |
| opensuse:tidy | 5.2.0-2.3 · openSUSE:Tumbleweed | Package registry (OSV) |
| suse:tidy | 1.0.20100204cvs-25.3 · SUSE:Linux Enterprise Software Development Kit 12 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
If successful
- Confidentiality
- P · data can be read
- Integrity
- P · data or configuration can be modified
- Availability
- P · the service can be disrupted
- Attack complexity
- M
- Confidentiality impact
- P
- Integrity impact
- P
- Availability impact
- P
Weakness class (CWE)
CWE-119 · Improper Restriction of Operations within the Bounds of a Memory BufferCVSS vector
AV:N/AC:M/Au:N/C:P/I:P/A:P
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
- Buffer Overflow via Environment VariablesCAPEC-10likelihood: High · High
- Overflow BuffersCAPEC-100likelihood: High · Very High
- Buffer ManipulationCAPEC-123likelihood: High · Very High
- Client-side Injection-induced Buffer OverflowCAPEC-14likelihood: Medium · High
- Filter Failure through Buffer OverflowCAPEC-24likelihood: High · High
- MIME ConversionCAPEC-42likelihood: High · High
- Overflow Binary Resource FileCAPEC-44likelihood: High · Very High
- Buffer Overflow via Symbolic LinksCAPEC-45likelihood: High · High
ATT&CK techniques
—
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- lists.apple.com/archives/security-announce/2015/Sep/msg00001.html
- lists.apple.com/archives/security-announce/2015/Sep/msg00005.html
- lists.apple.com/archives/security-announce/2015/Sep/msg00008.html
- www.debian.org/security/2015/dsa-3309
- www.securityfocus.com/bid/75037
- www.securitytracker.com/id/1033703
- www.ubuntu.com/usn/USN-2695-1
- support.apple.com/HT205212
- support.apple.com/HT205213
- support.apple.com/HT205267
Vendor advisories and official records. Exploit/PoC links are deliberately left out.