CVE-2026-34514

MEDIUMNVD 5.35.3
EchelonGraph scoreMEDIUM confidence

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

This medium-severity CVE scores 5.3 under NVD CVSS v3. EPSS exploit probability: 0.3% (25th percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.

Triggered by: Headline CVSS from NVD CVSS v3
Sources: EPSS, NVD CVSS v3
Trending — 3 sources updated this week

Also known asEUVD-2026-18037 (ENISA EUVD)Source: ENISA EUVD

5.3EG
EchelonGraph verdictMonitorRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.3%CVSS: 5.3Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, an attacker who controls the content_type parameter in aiohttp could use this to inject extra headers or similar exploits. This issue has been patched in version 3.13.4.

CVSS v3
5.3
EG Score
5.3MEDIUMmedium confidence
EG Risk
39
EG Risk 39/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity53% × 45%
Impact severity (EG Severity): CVSS 5.3 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.3% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
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 none (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
0.3%
EPSS %ILE
25th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (5.3): severity, escalated by confirmed exploitation. This CVE's 5.3 is its impact severity (EG Severity), not escalated.

EG Severity
5.3 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.NVD CVSS v3 · CVSS v3.0 or v3.1
EG Likelihood
0.3% within 30 daysSource: FIRST EPSS. FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at low or medium mission impact; Attend at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; 60 days if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.

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 none (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

April 1, 2026

Last Modified

October 26, 2026

Advisory Details (2)

Auto-updated Aug 6, 2026
Patch available. Sources: github_commit, github.
GitHub advisoryMentions a patch (unverified)

CRLF injection in multipart part content type header construction · Advisory · aio-libs/aiohttp · GitHub

https://github.com/aio-libs/aiohttp/security/advisories/GHSA-2vrm-gr82-f7m5
GitHub commit

commit 9a6ada97e2c6 (aio-libs/aiohttp)

Fix landed in aio-libs/aiohttp commit 9a6ada97e2c6 — awaiting tagged release

https://github.com/aio-libs/aiohttp/commit/9a6ada97e2c6cf1ce31727c6c9fcea17c21f6f06

Patch Availability(1)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
ubuntupython3-aiohttp (3.13.3-3ubuntu1+esm1) @ resolute2026-10-29ubuntu

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
python-aiohttp3.7.4-1, 3.7.4-1+deb11u1
  • every version up to 3.7.4-1+deb11u2: fixed in 3.7.4-1+deb11u2
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
python-aiohttp3.10.0-1 ... 3.9.5-1 (34 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
python-aiohttp3.11.16-1 ... 3.14.3-1 (16 versions)
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
python-aiohttp3.11.16-1 ... 3.13.3-3 (7 versions)
  • every version up to 3.13.5-1: fixed in 3.13.5-1
—
PyPI(1)
PackageVulnerable rangeFix by version rangeDependents
aiohttp0.1 ... 3.9.5 (304 versions)
  • every version up to 3.13.4: fixed in 3.13.4
—

Weakness Classification(1)

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

All Vendor Advisories

(1)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 12× in last 7d / 41× 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 98 of 213 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. 2 repeat rows among the latest 100 are merged into the row they repeat. The 115 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-29 16:33 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  2. 2026-10-29 16:14 UTCEG score recompute
  3. 2026-10-29 16:14 UTCVendor advisory
  4. 2026-10-28 16:32 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  5. 2026-10-27 16:31 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  6. 2026-10-26 22:27 UTCEG score recompute
  7. 2026-10-26 22:27 UTCVendor advisory
  8. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  9. 2026-10-25 16:32 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  10. 2026-10-25 14:33 UTCEG score recompute
  11. 2026-10-24 16:32 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  12. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  13. 2026-10-23 03:25 UTCEG score recompute
  14. 2026-10-23 03:25 UTCVendor advisory
  15. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  16. 2026-10-21 16:32 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  17. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  18. 2026-10-19 16:31 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  19. 2026-10-18 16:31 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  20. 2026-10-18 03:45 UTCEG score recompute
  21. 2026-10-17 16:34 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  22. 2026-10-16 16:41 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  23. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  24. 2026-10-14 16:32 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  25. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
Show 73 more
  1. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  2. 2026-10-12 16:12 UTCEG score recompute
  3. 2026-10-11 19:54 UTCEG score recompute
  4. 2026-10-11 17:08 UTCEG score recompute
  5. 2026-10-11 14:35 UTCEG score recompute
  6. 2026-10-11 13:48 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  7. 2026-10-11 02:31 UTCOSV refresh
  8. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  9. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  10. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  11. 2026-10-07 23:47 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  12. 2026-10-06 15:17 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  13. 2026-10-05 17:42 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  14. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  15. 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  16. 2026-10-01 19:49 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  17. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  18. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  19. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  20. 2026-09-26 15:58 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  21. 2026-09-26 00:26 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  22. 2026-09-21 14:19 UTCOSV refresh
  23. 2026-09-20 20:15 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  24. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  25. 2026-09-17 19:30 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  26. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  27. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  28. 2026-09-15 03:11 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  29. 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  30. 2026-09-12 15:01 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  31. 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  32. 2026-09-11 09:37 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  33. 2026-09-10 09:34 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  34. 2026-09-08 22:00 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  35. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  36. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  37. 2026-09-04 05:06 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  38. 2026-09-02 14:12 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  39. 2026-09-02 11:44 UTCOSV refresh
  40. 2026-09-01 13:53 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  41. 2026-09-01 04:39 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  42. 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  43. 2026-08-30 01:22 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  44. 2026-08-28 21:41 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  45. 2026-08-27 14:25 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  46. 2026-08-26 14:46 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  47. 2026-08-25 13:49 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  48. 2026-08-23 00:19 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  49. 2026-08-21 23:49 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  50. 2026-08-20 22:55 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  51. 2026-08-19 17:03 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  52. 2026-08-18 13:48 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  53. 2026-08-17 13:47 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  54. 2026-08-16 14:56 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  55. 2026-08-16 09:28 UTCEG score recompute
  56. 2026-08-16 09:28 UTCVendor advisory
  57. 2026-08-16 02:14 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  58. 2026-08-15 01:30 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  59. 2026-08-14 05:54 UTCEG score recompute
  60. 2026-08-14 05:54 UTCVendor advisory
  61. 2026-08-13 22:00 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  62. 2026-08-12 20:11 UTCEG score recompute
  63. 2026-08-12 20:11 UTCVendor advisory
  64. 2026-08-12 13:50 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  65. 2026-08-11 08:16 UTCEG score recompute
  66. 2026-08-11 08:16 UTCVendor advisory
  67. 2026-08-11 00:00 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  68. 2026-08-10 06:52 UTCEG score recompute
  69. 2026-08-10 06:52 UTCVendor advisory
  70. 2026-08-09 13:46 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  71. 2026-08-09 05:27 UTCEG score recompute
  72. 2026-08-09 05:27 UTCVendor advisory
  73. 2026-08-07 15:34 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-34514?
CVE-2026-34514 is a medium-severity vulnerability; its CVE record was published on April 1, 2026. AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, an attacker who controls the content_type parameter in aiohttp could use this to inject extra headers or similar exploits. This issue has been patched in version 3.13.4.
When was the CVE record for CVE-2026-34514 published?
The CVE record for CVE-2026-34514 was published on April 1, 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 October 26, 2026; the record at its source may have been updated since.
Is CVE-2026-34514 actively exploited?
CVE-2026-34514 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% probability of exploitation in the next 30 days (25th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-34514?
CVE-2026-34514 has a CVSS v3 base score of 5.3 (NVD).
How do I remediate CVE-2026-34514?
A fix for CVE-2026-34514 is available: update to the fixed version the vendor names in its advisory.

Dependency Blast Radius

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