Faktory is a language-agnostic background job server. In versions prior to 1.10.0, the server is vulnerable to an unauthenticated denial of service in which a single malformed command crashes the entire process. Its wire protocol is line-based, and several command handlers slice or index the received line at a fixed offset, such as cmd[5:] for PUSH or qs[0] for QUEUE, without checking that a payload is present. Sending a bare verb with no payload, for example PUSH, ACK, FAIL, BEAT, PUSHB, or QUEUE, triggers a Go slice or index out-of-range panic. Because the codebase has no recover() anywhere in the command-dispatch path, an unrecovered panic in a handler goroutine terminates the whole Go process rather than just that connection, instantly disconnecting every other client, worker, and in-flight job. The attack requires only a connection to the command port and completion of the trivial handshake, with no credentials when no password is configured, and can be repeated to keep the service down indefinitely. This issue is fixed in version 1.10.0.
CVE-2026-63403
“—” beside the score: it is equal to the CVSS score beside it.
This high-severity CVE scores 8.7 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.4% (36th percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.
- CISA's Vulnrichment rates exploitation as PoC; EchelonGraph holds no exploit-code reference for it
The CVE record names the fixed release — apply it.
- CVSS v3
- 8.7
- EG Score
- 8.7HIGHmedium confidence
- EG Risk
- 70EG Risk 70/100
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)Severity87% × 45%The EG Score, 8.7 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: The CVE record names the fixed release. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high. - EPSS PROB
- 0.4%
- EPSS %ILE
- 36th
- KEV
- Not listed
SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Attend at high (mission-essential systems).
The CVE record names the fixed release. 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
August 25, 2026
Last Modified
September 9, 2026
Advisory Details (2)
Auto-updated Aug 25, 2026Unauthenticated remote process crash via malformed wire-protocol commands (missing bounds checks, no panic recovery) · Advisory · contribsys/faktory · GitHub
https://github.com/contribsys/faktory/security/advisories/GHSA-gc57-f6pg-m9h6commit c2f17e390fc7 (contribsys/faktory)
Fix landed in contribsys/faktory commit c2f17e390fc7 — awaiting tagged release
http://github.com/contribsys/faktory/commit/c2f17e390fc7d38b6ece82b8da23f5ca15646212Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 16× in last 7d / 49× 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.
- 2026-10-11 19:33 UTCEG score recompute
- 2026-10-11 16:48 UTCEG score recompute
- 2026-10-11 14:10 UTCEG score recompute
- 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.4% · 36th percentile
- 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.4% · 36th percentile
- 2026-10-10 11:09 UTCEG score recompute
- 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.4% · 36th percentile
- 2026-10-09 03:41 UTCEG score recompute
- 2026-10-08 17:13 UTCEPSS rescoreEPSS 0.4% · 36th percentile
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- 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.4% · 36th percentile
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- 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.4% · 36th percentile
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- 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.4% · 36th percentile
- 2026-10-03 16:16 UTCEG score recompute
- 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.4% · 36th percentile
- 2026-10-03 01:45 UTCEG score recompute
- 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.4% · 36th percentile
- 2026-10-01 22:40 UTCEG score recompute
- 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.4% · 36th percentile
- 2026-09-30 20:09 UTCEG score recompute
- 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.4% · 36th percentile
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- 2026-09-30 06:21 UTCEG score recompute
- 2026-09-29 01:35 UTCEG score recompute
- 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.4% · 36th percentile
- 2026-09-27 23:49 UTCEG score recompute
- 2026-09-26 21:32 UTCEG score recompute
- 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.4% · 36th percentile
- 2026-09-25 00:18 UTCEG score recompute
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- 2026-09-23 17:54 UTCEPSS rescoreEPSS 0.4% · 36th percentile
- 2026-09-22 20:29 UTCEG score recompute
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- 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.4% · 36th percentile
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- 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.4% · 36th percentile
- 2026-09-18 00:26 UTCEG score recompute
- 2026-09-16 22:39 UTCEG score recompute
- 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.4% · 36th percentile
- 2026-09-16 09:20 UTCEG score recompute
- 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.4% · 36th percentile
- 2026-09-15 06:08 UTCEG score recompute
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- 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.4% · 35th percentile
- 2026-09-11 11:57 UTCEG score recompute
- 2026-09-11 09:37 UTCEPSS rescoreEPSS 0.4% · 35th percentile
- 2026-09-10 10:07 UTCEG score recompute
- 2026-09-09 00:56 UTCEG score recompute
- 2026-09-08 22:01 UTCEPSS rescoreEPSS 0.4% · 35th percentile
- 2026-09-07 18:20 UTCEG score recompute
- 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.4% · 35th percentile
- 2026-09-06 16:22 UTCEG score recompute
- 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.4% · 35th percentile
- 2026-09-06 03:29 UTCEG score recompute
- 2026-09-05 15:31 UTCEPSS rescoreEPSS 0.4% · 35th percentile
- 2026-09-05 01:43 UTCEG score recompute
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- 2026-09-04 05:07 UTCEPSS rescoreEPSS 0.4% · 35th percentile
- 2026-09-02 21:39 UTCEG score recompute
- 2026-09-02 14:12 UTCEPSS rescoreEPSS 0.4% · 35th percentile
- 2026-09-01 19:48 UTCEG score recompute
- 2026-09-01 13:54 UTCEPSS rescoreEPSS 0.4% · 35th percentile
- 2026-09-01 06:25 UTCEG score recompute
- 2026-09-01 04:40 UTCEPSS rescoreEPSS 0.4% · 35th percentile
- 2026-08-31 03:38 UTCEG score recompute
- 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.4% · 35th percentile
- 2026-08-30 01:53 UTCEG score recompute
- 2026-08-30 01:22 UTCEPSS rescoreEPSS 0.4% · 35th percentile
- 2026-08-29 00:02 UTCEG score recompute
- 2026-08-28 21:42 UTCEPSS rescoreEPSS 0.4% · 35th percentile
- 2026-08-27 18:07 UTCEG score recompute
- 2026-08-27 14:25 UTCEPSS rescoreEPSS 0.4% · 35th percentile
- 2026-08-26 15:56 UTCEG score recompute
- 2026-08-26 14:46 UTCEPSS rescoreEPSS 0.4% · 35th percentile
- 2026-08-26 14:44 UTCEG score recompute
- 2026-08-25 22:29 UTCEG score recompute
- 2026-08-25 22:10 UTCEG score recomputeFirst assessed: 8.7 HIGH
- 2026-08-25 22:09 UTCMITRE cvelistV5first tracked
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Frequently asked(5)
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Dependency Blast Radius
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