Soup Sieve is a CSS selector library designed to be used with Beautiful Soup 4. Prior to 2.8.4, the CSS selector parser in soupsieve allocates unbounded memory when compiling large comma-separated selector lists, allowing an attacker who can supply a crafted selector string to soupsieve.compile() or Beautiful Soup .select() / .select_one() to allocate hundreds of megabytes of heap memory from a relatively small input and cause denial of service. This issue is fixed in version 2.8.4.
CVE-2026-49476
This high-severity CVE scores 7.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.6%, top 55% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
- High severity, but no confirmed exploitation yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 7.5
- EG Score
- 7.5(medium)
- EPSS
- 44.8%
- KEV
- Not listed
Published
July 9, 2026
Last Modified
July 15, 2026
Advisory Details (3)
Auto-updated Jul 15, 2026Memory Exhaustion via Large Comma-Separated Selector Lists in soupsieve · Advisory · facelessuser/soupsieve · GitHub
https://github.com/facelessuser/soupsieve/security/advisories/GHSA-2wc2-fm75-p42x2.8.4
Patch available: facelessuser/soupsieve 2.8.4
https://github.com/facelessuser/soupsieve/releases/tag/2.8.4commit 28108ab80581 (facelessuser/soupsieve)
Patch available: facelessuser/soupsieve 2.8.4 (contains commit 28108ab80581)
https://github.com/facelessuser/soupsieve/commit/28108ab805818c832d9568142a99844fd95a0d39Vendor Advisories for CVE-2026-49476(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Weakness Classification(2)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 15× in last 7d / 15× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-15 20:15 UTCEG score recompute
- 2026-07-15 16:57 UTCEPSS rescore
- 2026-07-15 16:57 UTCEPSS rescore
- 2026-07-15 07:44 UTCEG score recompute
- 2026-07-14 19:08 UTCEG score recompute
- 2026-07-14 06:30 UTCEG score recompute
- 2026-07-13 17:57 UTCEG score recompute
- 2026-07-13 05:26 UTCEG score recompute
- 2026-07-12 16:55 UTCEG score recompute
- 2026-07-12 04:22 UTCEG score recompute
- 2026-07-11 15:50 UTCEG score recompute
- 2026-07-11 03:19 UTCEG score recompute
- 2026-07-10 14:48 UTCEG score recompute
- 2026-07-10 02:17 UTCEG score recompute
- 2026-07-09 13:45 UTCEG score recompute
Related CVEs(same CWE)
Same CWE
10 shownCWE-400
Frequently asked(5)
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Dependency Blast Radius
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