CVE-2026-54735

CRITICALPre-NVD 10.010.0
EchelonGraph scoreMEDIUM confidence

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

This critical-severity CVE scores 10.0 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

Also known asEUVD-2026-50401 (ENISA EUVD) · GHSA-4p3g-4hcj-wpvx (GitHub Security Advisories)Source: ENISA EUVD

10.0EG
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).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.6%CVSS: 10.0Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

Prebid Server is an open-source solution for running real-time advertising auctions in the cloud. Prior to version 4.4.0, certain bidder adapters in Prebid Server interpolate user-supplied parameters into outbound request URLs without properly validating host and subdomain values, allowing crafted bid request parameters to cause server-side requests to unintended destinations and potentially expose internal network services or sensitive server endpoints. This issue is fixed in version 4.4.0.

CVSS v3
10.0
EG Score
10.0CRITICALmedium confidence
EG Risk
60
EG Risk 60/100

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)
Severity100% × 45%
Impact severity (EG Severity): CVSS 10.0 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.6% × 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 total (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

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

The EG score (10.0): severity, escalated by confirmed exploitation. This CVE's 10.0 is its impact severity (EG Severity), not escalated.

EG Severity
10.0 CRITICALCVSS-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
0.6% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-30). 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: 3 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 total (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)3 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 total (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 29, 2026

Last Modified

October 23, 2026

Advisory Details (4)

Auto-updated Oct 31, 2026
Patch available. Sources: github_commit, github_pr, github_release, github.
GitHub advisoryMentions a patch (unverified)

Request forgery vulnerability allows for possible host environment data extraction · Advisory · prebid/prebid-server · GitHub

https://github.com/prebid/prebid-server/security/advisories/GHSA-4p3g-4hcj-wpvx
GitHub release Patch Available

v4.4.0

Patch available: prebid/prebid-server v4.4.0

https://github.com/prebid/prebid-server/releases/tag/v4.4.0
GitHub pull request Patch Available

Validate host & subdomain bidder params

Patch available: prebid/prebid-server v4.4.0 (PR #4802 merged 2026-06-05)

https://github.com/prebid/prebid-server/pull/4802
GitHub commit Patch Available

commit 494ac271cd4b (prebid/prebid-server)

Patch available: prebid/prebid-server v4.4.0 (contains commit 494ac271cd4b)

https://github.com/prebid/prebid-server/commit/494ac271cd4b5024df9123ef25ca3cff96390be3

Vendor Advisories for CVE-2026-54735(1)

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

Affected Packages

(4 across 1 ecosystem)
Go(4)
PackageVulnerable rangeFix by version rangeDependents
github.com/prebid/prebid-server—
  • every version through 0.275.0: no fix on record
—
github.com/prebid/prebid-server/v2—
  • every version through 2.32.0: no fix on record
—
github.com/prebid/prebid-server/v3—
  • every version through 3.30.0: no fix on record
—
github.com/prebid/prebid-server/v4—
  • every version up to 4.4.0: fixed in 4.4.0
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 15× in last 7d / 59× 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 170 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 70 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-31 09:21 UTCEG score recompute
  2. 2026-10-30 16:34 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  3. 2026-10-30 08:31 UTCEG score recompute
  4. 2026-10-29 16:33 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  5. 2026-10-29 07:42 UTCEG score recompute
  6. 2026-10-28 16:32 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  7. 2026-10-28 06:52 UTCEG score recompute
  8. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  9. 2026-10-27 06:03 UTCEG score recompute
  10. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  11. 2026-10-26 01:07 UTCEG score recompute
  12. 2026-10-25 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  13. 2026-10-25 14:19 UTCEG score recompute
  14. 2026-10-25 00:16 UTCEG score recompute
  15. 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  16. 2026-10-23 23:27 UTCEG score recompute
  17. 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  18. 2026-10-22 23:56 UTCEG score recompute
  19. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  20. 2026-10-21 23:02 UTCEG score recompute
  21. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  22. 2026-10-20 22:10 UTCEG score recompute
  23. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  24. 2026-10-19 21:18 UTCEG score recompute
  25. 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
Show 75 more
  1. 2026-10-18 20:22 UTCEG score recompute
  2. 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  3. 2026-10-18 03:30 UTCEG score recompute
  4. 2026-10-17 19:32 UTCEG score recompute
  5. 2026-10-17 16:34 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  6. 2026-10-16 18:41 UTCEG score recompute
  7. 2026-10-16 16:42 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  8. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  9. 2026-10-15 15:35 UTCEG score recompute
  10. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  11. 2026-10-14 09:52 UTCEG score recompute
  12. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  13. 2026-10-13 07:48 UTCEG score recompute
  14. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  15. 2026-10-12 15:56 UTCEG score recompute
  16. 2026-10-11 19:39 UTCEG score recompute
  17. 2026-10-11 16:54 UTCEG score recompute
  18. 2026-10-11 14:17 UTCEG score recompute
  19. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  20. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  21. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  22. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  23. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  24. 2026-10-07 00:00 UTCEG score recompute
  25. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  26. 2026-10-05 20:51 UTCEG score recompute
  27. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  28. 2026-10-05 02:36 UTCEG score recompute
  29. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  30. 2026-10-04 07:01 UTCEG score recompute
  31. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  32. 2026-10-02 17:57 UTCEG score recompute
  33. 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  34. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  35. 2026-10-01 03:34 UTCEG score recompute
  36. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  37. 2026-09-29 15:22 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  38. 2026-09-29 07:35 UTCEG score recompute
  39. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  40. 2026-09-28 03:13 UTCEG score recompute
  41. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  42. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  43. 2026-09-25 05:38 UTCEG score recompute
  44. 2026-09-24 14:04 UTCEPSS rescoreEPSS 0.6% · 46th percentile
  45. 2026-09-23 21:49 UTCEG score recompute
  46. 2026-09-23 17:54 UTCEPSS rescoreEPSS 0.3% · 28th percentile
  47. 2026-09-22 15:48 UTCEG score recompute
  48. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.3% · 28th percentile
  49. 2026-09-20 00:23 UTCEG score recompute
  50. 2026-09-18 22:42 UTCEG score recompute
  51. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.3% · 28th percentile
  52. 2026-09-18 01:40 UTCEG score recompute
  53. 2026-09-17 19:31 UTCEPSS rescoreEPSS 0.3% · 28th percentile
  54. 2026-09-17 01:35 UTCEG score recompute
  55. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.3% · 27th percentile
  56. 2026-09-16 05:48 UTCEG score recompute
  57. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.3% · 27th percentile
  58. 2026-09-15 07:54 UTCEG score recompute
  59. 2026-09-15 03:11 UTCEPSS rescoreEPSS 0.3% · 27th percentile
  60. 2026-09-13 19:53 UTCEG score recompute
  61. 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.3% · 27th percentile
  62. 2026-09-12 16:11 UTCEG score recompute
  63. 2026-09-11 15:06 UTCEG score recompute
  64. 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.3% · 27th percentile
  65. 2026-09-10 13:04 UTCEG score recompute
  66. 2026-09-10 09:35 UTCEPSS rescoreEPSS 0.3% · 27th percentile
  67. 2026-09-09 07:47 UTCEG score recompute
  68. 2026-09-08 22:01 UTCEPSS rescoreEPSS 0.3% · 27th percentile
  69. 2026-09-07 20:47 UTCEG score recompute
  70. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.3% · 27th percentile
  71. 2026-09-06 14:16 UTCEG score recompute
  72. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.3% · 27th percentile
  73. 2026-09-05 19:06 UTCEG score recompute
  74. 2026-09-04 16:17 UTCEG score recompute
  75. 2026-09-04 11:55 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-54735?
CVE-2026-54735 is a critical-severity vulnerability; its CVE record was published on July 29, 2026. Prebid Server is an open-source solution for running real-time advertising auctions in the cloud. Prior to version 4.4.0, certain bidder adapters in Prebid Server interpolate user-supplied parameters into outbound request URLs without properly validating host and subdomain values, allowing crafted…
When was the CVE record for CVE-2026-54735 published?
The CVE record for CVE-2026-54735 was published on July 29, 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-2026-54735 actively exploited?
CVE-2026-54735 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-2026-54735?
CVE-2026-54735 has a CVSS base score of 10.0 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-54735?
A fix for CVE-2026-54735 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-54735 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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