CVE-2026-11809

LOWPre-NVD 3.73.7
EchelonGraph scoreMEDIUM confidence

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

This low-severity CVE scores 3.7 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.4% (29th 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

Also known asEUVD-2026-55843 (ENISA EUVD)Source: ENISA EUVD

3.7EG
EchelonGraph verdictMonitorNo release containing the referenced fix is confirmed: check the referenced fix and the vendor's advisory for a release that contains it; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule (the SSVC decision on this page).
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.4%CVSS: 3.7Exploit: None knownExposed services: Not assessed

A fix is referenced (a reference tagged "Patch", often a source commit), but no release containing it is confirmed — find the release that contains it; until it is applied, mitigate (WAF / firewall / segmentation).

The UpdateHub OTA client in subsys/mgmt/updatehub/updatehub.c contains an out-of-bounds / uninitialized-memory read in z_impl_updatehub_probe(). The probe response from the UpdateHub server is copied into a heap buffer (metadata) that is correctly NUL-terminated, but a second buffer (metadata_copy) is allocated with k_malloc (unzeroed) and filled with memcpy(metadata_copy, metadata, strlen(metadata)), which omits the terminating NUL. Everything after the copied content remains uninitialized heap.

When the first json_obj_parse() over the array descriptor fails, the code falls back to json_obj_parse(metadata_copy, strlen(metadata_copy), ...). The strlen() call scans past the copied bytes through uninitialized heap and, if no zero byte is found before the end of the allocation, reads beyond the buffer; the resulting over-long length is then parsed as JSON. The probe payload is fully controlled by the (malicious, compromised, or — without the optional CONFIG_UPDATEHUB_DTLS — on-path) UpdateHub server, which can craft a large payload that fails the first parse to drive this path.

The consequence is a read of uninitialized heap, with a worst case of an out-of-bounds read past the metadata_copy allocation that can fault and crash the update thread/device, producing a network-triggerable denial of service. The over-read data is consumed only internally to evaluate the update and is not returned to the attacker, so there is no direct information disclosure and no out-of-bounds write.

The fix zeroes metadata_copy with memset before the copy, guaranteeing NUL termination and bounding strlen() within the allocation.

CVSS v3
3.7
EG Score
3.7LOWmedium confidence
EG Risk
17
EG Risk 17/100

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)
Severity37% × 45%
Impact severity (EG Severity): CVSS 3.7 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.4% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at every mission impact level.
Exploitation none (CISA Vulnrichment) · Automatable no (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 referenced, but no release containing it is confirmed. Check the referenced fix and the vendor's advisory for a release that contains it; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule.
EPSS PROB
0.4%
EPSS %ILE
29th
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 (3.7): severity, escalated by confirmed exploitation. This CVE's 3.7 is its impact severity (EG Severity), not escalated.

EG Severity
3.7 LOWCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.a secondary CVSS source · CVSS v3.0 or v3.1
EG Likelihood
0.4% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-24). 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 every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says. In the directive's words, “Fix on system upgrade” means that, “unless conditions change”, the vulnerability “should be remediated the next time the vulnerable asset receives a scheduled major upgrade or rebuild”: its timelines are “dynamic as facts change”, and a KEV listing shortens them.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.

A fix is referenced, but no release containing it is confirmed. Check the referenced fix and the vendor's advisory for a release that contains it; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule.

Exploitation none (CISA Vulnrichment) · Automatable no (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)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says. In the directive's words, “Fix on system upgrade” means that, “unless conditions change”, the vulnerability “should be remediated the next time the vulnerable asset receives a scheduled major upgrade or rebuild”: its timelines are “dynamic as facts change”, and a KEV listing shortens them.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (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

August 10, 2026

Last Modified

October 23, 2026

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 7× in last 7d / 38× 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.

  1. 2026-11-01 16:33 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  2. 2026-10-31 16:32 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  3. 2026-10-30 16:33 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  4. 2026-10-29 16:32 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  5. 2026-10-28 16:31 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  6. 2026-10-27 16:31 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  7. 2026-10-26 16:30 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  8. 2026-10-25 16:32 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  9. 2026-10-25 14:50 UTCEG score recompute
  10. 2026-10-24 16:32 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  11. 2026-10-23 19:34 UTCEG score recompute
  12. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  13. 2026-10-22 16:33 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  14. 2026-10-21 16:32 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  15. 2026-10-20 16:32 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  16. 2026-10-19 16:31 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  17. 2026-10-18 16:31 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  18. 2026-10-18 05:04 UTCEG score recompute
  19. 2026-10-17 16:33 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  20. 2026-10-16 16:40 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  21. 2026-10-15 16:31 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  22. 2026-10-14 16:32 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  23. 2026-10-13 16:33 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  24. 2026-10-12 16:37 UTCEG score recompute
  25. 2026-10-12 16:33 UTCEPSS rescoreEPSS 0.4% · 27th percentile
Show 71 more
  1. 2026-10-11 20:13 UTCEG score recompute
  2. 2026-10-11 18:25 UTCEG score recompute
  3. 2026-10-11 14:58 UTCEG score recompute
  4. 2026-10-11 13:48 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  5. 2026-10-10 19:59 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  6. 2026-10-09 20:06 UTCEPSS rescoreEPSS 0.4% · 26th percentile
  7. 2026-10-08 17:11 UTCEPSS rescoreEPSS 0.4% · 26th percentile
  8. 2026-10-07 23:47 UTCEPSS rescoreEPSS 0.4% · 26th percentile
  9. 2026-10-06 15:17 UTCEPSS rescoreEPSS 0.4% · 26th percentile
  10. 2026-10-05 17:42 UTCEPSS rescoreEPSS 0.4% · 26th percentile
  11. 2026-10-04 23:21 UTCEPSS rescoreEPSS 0.4% · 26th percentile
  12. 2026-10-04 04:17 UTCEG score recompute
  13. 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.4% · 26th percentile
  14. 2026-10-01 19:49 UTCEPSS rescoreEPSS 0.4% · 26th percentile
  15. 2026-09-30 22:24 UTCEG score recompute
  16. 2026-09-30 15:02 UTCEPSS rescoreEPSS 0.4% · 26th percentile
  17. 2026-09-29 15:20 UTCEPSS rescoreEPSS 0.4% · 26th percentile
  18. 2026-09-28 13:50 UTCEPSS rescoreEPSS 0.4% · 26th percentile
  19. 2026-09-27 12:30 UTCEG score recompute
  20. 2026-09-26 15:58 UTCEPSS rescoreEPSS 0.4% · 26th percentile
  21. 2026-09-23 22:11 UTCEG score recompute
  22. 2026-09-23 13:47 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  23. 2026-09-20 20:15 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  24. 2026-09-20 19:57 UTCEG score recompute
  25. 2026-09-18 19:27 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  26. 2026-09-17 14:53 UTCEG score recompute
  27. 2026-09-16 05:14 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  28. 2026-09-14 09:01 UTCEG score recompute
  29. 2026-09-13 16:46 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  30. 2026-09-12 15:00 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  31. 2026-09-11 14:52 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  32. 2026-09-11 09:36 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  33. 2026-09-11 06:47 UTCEG score recompute
  34. 2026-09-10 09:34 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  35. 2026-09-08 22:00 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  36. 2026-09-08 04:33 UTCEG score recompute
  37. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  38. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  39. 2026-09-05 01:51 UTCEG score recompute
  40. 2026-09-04 05:06 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  41. 2026-09-02 14:11 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  42. 2026-09-01 23:06 UTCEG score recompute
  43. 2026-09-01 13:53 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  44. 2026-09-01 04:39 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  45. 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  46. 2026-08-30 01:21 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  47. 2026-08-29 20:52 UTCEG score recompute
  48. 2026-08-28 21:40 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  49. 2026-08-27 14:24 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  50. 2026-08-26 17:27 UTCEG score recompute
  51. 2026-08-25 13:48 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  52. 2026-08-24 00:35 UTCEG score recompute
  53. 2026-08-23 00:19 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  54. 2026-08-21 23:48 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  55. 2026-08-20 22:55 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  56. 2026-08-20 22:21 UTCEG score recompute
  57. 2026-08-19 17:03 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  58. 2026-08-18 13:48 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  59. 2026-08-17 20:07 UTCEG score recompute
  60. 2026-08-16 14:56 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  61. 2026-08-16 02:14 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  62. 2026-08-15 01:30 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  63. 2026-08-14 17:50 UTCEG score recompute
  64. 2026-08-13 22:00 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  65. 2026-08-12 13:50 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  66. 2026-08-11 15:36 UTCEG score recompute
  67. 2026-08-11 14:57 UTCEG score recompute
  68. 2026-08-11 13:42 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  69. 2026-08-10 21:32 UTCEG score recompute
  70. 2026-08-10 20:55 UTCEG score recomputeFirst assessed: 3.7 LOW
  71. 2026-08-10 20:54 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-11809?
CVE-2026-11809 is a low-severity vulnerability; its CVE record was published on August 10, 2026. The UpdateHub OTA client in subsys/mgmt/updatehub/updatehub.c contains an out-of-bounds / uninitialized-memory read in z_impl_updatehub_probe(). The probe response from the UpdateHub server is copied into a heap buffer (metadata) that is correctly NUL-terminated, but a second buffer (metadata_copy)…
When was the CVE record for CVE-2026-11809 published?
The CVE record for CVE-2026-11809 was published on August 10, 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 23, 2026; the record at its source may have been updated since.
Is CVE-2026-11809 actively exploited?
CVE-2026-11809 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.4% probability of exploitation in the next 30 days (29th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-11809?
CVE-2026-11809 has a CVSS base score of 3.7 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-11809?
A fix for CVE-2026-11809 is referenced (a reference tagged "Patch", often a source commit), but EchelonGraph has no release containing it on record. Check that reference and the vendor's advisory for a release that contains the fix and update to it; until then, restrict network exposure of the affected system or apply the vendor's mitigation.

Dependency Blast Radius

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