CVE-2026-49477

HIGHPre-NVD 7.57.5
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to the CVSS score beside it.

This high-severity CVE scores 7.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.6% (49th percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.

Triggered by: Headline CVSS from a secondary CVSS source
Sources: EPSS, a secondary CVSS source
Elevated
7.5EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • CISA's Vulnrichment rates exploitation as PoC; EchelonGraph holds no exploit-code reference for it
CISA-KEV: Not listedEPSS PROB: 0.6%CVSS: 7.5Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

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 contains a regular expression vulnerable to catastrophic backtracking when processing an attribute selector with an unterminated quoted value in soupsieve/css_parser.py, allowing an attacker who can supply untrusted CSS selector strings to soupsieve.compile() or Beautiful Soup .select() / .select_one() to cause CPU exhaustion and denial of service. This issue is fixed in version 2.8.4.

CVSS v3
7.5
EG Score
7.5HIGHmedium confidence
EG Risk
65
EG Risk 65/100

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed (value × EchelonGraph’s weight)
Severity75% × 45%
The EG Score, 7.5 of 10.
Exploitation40% × 40%
EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).
Exploitation public PoC (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
0.6%
EPSS %ILE
49th
KEV
Not listed

SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Attend at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation public PoC (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; 60 days if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

July 9, 2026

Last Modified

July 28, 2026

Advisory Details (3)

Auto-updated Jul 15, 2026
Patch available. Sources: github_commit, github_release, github.
GitHub advisoryMentions a patch (unverified)

Regular Expression Denial of Service (ReDoS) in soupsieve Selector Parser · Advisory · facelessuser/soupsieve · GitHub

https://github.com/facelessuser/soupsieve/security/advisories/GHSA-836r-79rf-4m37
GitHub release Patch Available

2.8.4

Patch available: facelessuser/soupsieve 2.8.4

https://github.com/facelessuser/soupsieve/releases/tag/2.8.4
GitHub commit Patch Available

commit eb4397618709 (facelessuser/soupsieve)

Patch available: facelessuser/soupsieve 2.8.4 (contains commit eb4397618709)

https://github.com/facelessuser/soupsieve/commit/eb4397618709186c109400448c6043b728217dc3

Vendor Advisories for CVE-2026-49477(11)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(9)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatquay/quay-rhel8:17885938432026-09-22redhat
redhatquay/quay-rhel9:17895637532026-09-21redhat
redhatquay/quay-rhel8:17885943762026-09-10redhat
redhatquay/quay-rhel8:17885618412026-09-09redhat
redhatquay/quay-rhel8:17885955742026-09-08redhat
redhatquay/quay-rhel8:17881917552026-09-03redhat
redhatrhoai/odh-workbench-jupyter-trustyai-cpu-py312-rhel9:17870735932026-08-27redhat
redhatpython-rpds-py-main-2026.6.3-1.hum12026-07-01redhat
redhatpython-attrs-main-26.1.0-3.hum12026-06-07redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(5 across 5 ecosystems)
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
soupsieve2.2.1-1 ... 2.8.4-1 (15 versions)
  • every version on: no fix on record
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
soupsieve2.3.2-1 ... 2.8.4-1 (11 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
soupsieve2.7-1, 2.7-2, 2.8.1-1, 2.8.3-1, 2.8.4-1
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
soupsieve2.7-1, 2.7-2, 2.8.1-1, 2.8.3-1
  • every version up to 2.8.4-1: fixed in 2.8.4-1
—
PyPI(1)
PackageVulnerable rangeFix by version rangeDependents
soupsieve0.4 ... 2.8.3 (51 versions)
  • every version up to 2.8.4: fixed in 2.8.4
—

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 11× in last 7d / 35× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 100 of 202 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 102 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  2. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  3. 2026-10-12 16:00 UTCEG score recompute
  4. 2026-10-11 19:43 UTCEG score recompute
  5. 2026-10-11 16:57 UTCEG score recompute
  6. 2026-10-11 14:21 UTCEG score recompute
  7. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  8. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  9. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  10. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  11. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  12. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  13. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  14. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  15. 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  16. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  17. 2026-10-01 16:03 UTCEG score recompute
  18. 2026-10-01 16:03 UTCVendor advisory
  19. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  20. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  21. 2026-09-28 10:58 UTCEG score recompute
  22. 2026-09-28 10:58 UTCVendor advisory
  23. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  24. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  25. 2026-09-26 00:27 UTCEPSS rescoreEPSS 0.6% · 48th percentile
Show 75 more
  1. 2026-09-24 11:40 UTCEG score recompute
  2. 2026-09-24 11:40 UTCVendor advisory
  3. 2026-09-23 17:53 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  4. 2026-09-23 05:59 UTCEG score recompute
  5. 2026-09-23 05:59 UTCVendor advisory
  6. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  7. 2026-09-18 05:37 UTCEG score recompute
  8. 2026-09-18 05:37 UTCVendor advisory
  9. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  10. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  11. 2026-09-13 23:46 UTCEG score recompute
  12. 2026-09-13 23:46 UTCVendor advisory
  13. 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  14. 2026-09-13 08:20 UTCVendor advisory
  15. 2026-09-12 15:50 UTCEG score recompute
  16. 2026-09-12 15:50 UTCVendor advisory
  17. 2026-09-12 03:25 UTCEG score recompute
  18. 2026-09-12 03:25 UTCVendor advisory
  19. 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  20. 2026-09-10 09:35 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  21. 2026-09-08 22:01 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  22. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  23. 2026-09-06 14:00 UTCEG score recompute
  24. 2026-09-06 14:00 UTCVendor advisory
  25. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  26. 2026-09-05 22:36 UTCEG score recompute
  27. 2026-09-05 22:36 UTCVendor advisory
  28. 2026-09-04 05:06 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  29. 2026-09-02 14:12 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  30. 2026-09-01 13:54 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  31. 2026-09-01 04:40 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  32. 2026-08-30 19:22 UTCEG score recompute
  33. 2026-08-30 19:22 UTCVendor advisory
  34. 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  35. 2026-08-30 06:56 UTCEG score recompute
  36. 2026-08-30 06:56 UTCVendor advisory
  37. 2026-08-30 01:22 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  38. 2026-08-28 21:41 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  39. 2026-08-27 21:46 UTCEG score recompute
  40. 2026-08-27 21:46 UTCVendor advisory
  41. 2026-08-27 14:25 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  42. 2026-08-27 01:10 UTCEG score recompute
  43. 2026-08-27 01:10 UTCVendor advisory
  44. 2026-08-26 14:46 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  45. 2026-08-26 03:53 UTCEG score recompute
  46. 2026-08-26 03:53 UTCVendor advisory
  47. 2026-08-25 13:49 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  48. 2026-08-25 10:07 UTCVendor advisory
  49. 2026-08-24 20:21 UTCEG score recompute
  50. 2026-08-24 20:21 UTCVendor advisory
  51. 2026-08-24 06:54 UTCVendor advisory
  52. 2026-08-23 18:28 UTCVendor advisory
  53. 2026-08-23 06:03 UTCEG score recompute
  54. 2026-08-23 06:03 UTCVendor advisory
  55. 2026-08-23 00:19 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  56. 2026-08-22 17:36 UTCVendor advisory
  57. 2026-08-22 05:10 UTCEG score recompute
  58. 2026-08-22 05:10 UTCVendor advisory
  59. 2026-08-21 23:49 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  60. 2026-08-21 16:43 UTCVendor advisory
  61. 2026-08-21 03:51 UTCEG score recompute
  62. 2026-08-21 03:51 UTCVendor advisory
  63. 2026-08-20 22:55 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  64. 2026-08-20 15:17 UTCVendor advisory
  65. 2026-08-20 01:50 UTCEG score recompute
  66. 2026-08-20 01:50 UTCVendor advisory
  67. 2026-08-19 17:04 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  68. 2026-08-19 09:16 UTCVendor advisory
  69. 2026-08-18 20:43 UTCEG score recompute
  70. 2026-08-18 20:43 UTCVendor advisory
  71. 2026-08-18 13:48 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  72. 2026-08-18 02:55 UTCEG score recompute
  73. 2026-08-18 02:55 UTCVendor advisory
  74. 2026-08-17 13:47 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  75. 2026-08-17 13:36 UTCVendor advisory

Related CVEs(same product + same vendor + same CWE)

Same product

3 shown

Debian:11:soupsieve · Debian:12:soupsieve

Frequently asked(5)

What is CVE-2026-49477?
CVE-2026-49477 is a high-severity vulnerability; its CVE record was published on July 9, 2026. 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 contains a regular expression vulnerable to catastrophic backtracking when processing an attribute selector with an unterminated quoted value in…
When was the CVE record for CVE-2026-49477 published?
The CVE record for CVE-2026-49477 was published on July 9, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of July 28, 2026; the record at its source may have been updated since.
Is CVE-2026-49477 actively exploited?
CVE-2026-49477 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.6% probability of exploitation in the next 30 days (49th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-49477?
CVE-2026-49477 has a CVSS base score of 7.5 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-49477?
A fix for CVE-2026-49477 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-49477 are linked in the Vendor Advisories panel on this page.

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