Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Due to a NULL pointer dereference bug Squid is vulnerable to a Denial of Service attack against Squid's Gopher gateway. The gopher protocol is always available and enabled in Squid prior to Squid 6.0.1. Responses triggering this bug are possible to be received from any gopher server, even those without malicious intent. Gopher support has been removed in Squid version 6.0.1. Users are advised to upgrade. Users unable to upgrade should reject all gopher URL requests.
CVE-2023-46728
“—” beside the score: it is equal to NVD's CVSS score.
This high-severity CVE scores 7.5 under NVD CVSS v3. EPSS exploit probability: 6.0% (93rd percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.
- High severity, but no confirmed exploitation yet
A fix is available — apply it.
- CVSS v3
- 7.5
- EG Score
- 7.5HIGHmedium confidence
- EG Risk
- 51EG Risk 51/100
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)Severity75% × 45%Impact severity (EG Severity): CVSS 7.5 of 10. Never the KEV-floored or EPSS-lifted EG Score.Exploitation6.0% × 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
- 6.0%
- EPSS %ILE
- 93rd
- 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 (7.5): severity, escalated by confirmed exploitation. This CVE's 7.5 is its impact severity (EG Severity), not escalated.
- EG Severity
- 7.5 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.NVD CVSS v3 · CVSS v3.0 or v3.1
- EG Likelihood
- 6.0% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-20). 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
November 6, 2023
Last Modified
June 17, 2026
References (6)
- security-advisories@github · CVE Programhttps://github.com/squid-cache/squid/commit/6ea12e8fb590ac6959e9356a81aa3370576568c3Patch
- security-advisories@github · CVE Programhttps://github.com/squid-cache/squid/security/advisories/GHSA-cg5h-v6vc-w33fVendor Advisory
- security-advisories@github · CVE Programhttps://lists.fedoraproject.org/archives/list/[email protected]/message/A5QASTMCUSUEW3UOMKHZJB3FTONWSRXS/
- security-advisories@github · CVE Programhttps://lists.fedoraproject.org/archives/list/[email protected]/message/MEV66D3PAAY6K7TWDT3WZBLCPLASFJDC/
- security-advisories@github · CVE Programhttps://security.netapp.com/advisory/ntap-20231214-0006/
- CVE Programhttps://lists.debian.org/debian-lts-announce/2025/09/msg00027.html
Vendor Advisories for CVE-2023-46728(9)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
- RHSA-2024:1787Red Hat Product SecurityHigh
Red Hat Security Advisory: squid security update
- RHSA-2024:1153Red Hat Product SecurityHigh
Red Hat Security Advisory: squid security update
- RHSA-2024:0771Red Hat Product SecurityHigh
Red Hat Security Advisory: squid:4 security update
- RHSA-2024:0773Red Hat Product SecurityHigh
Red Hat Security Advisory: squid:4 security update
- RHSA-2024:0772Red Hat Product SecurityHigh
Red Hat Security Advisory: squid:4 security update
- RHSA-2024:0397Red Hat Product SecurityHigh
Red Hat Security Advisory: squid:4 security update
- RHSA-2024:0071Red Hat Product SecurityHigh
Red Hat Security Advisory: squid security update
- RHSA-2024:0072Red Hat Product SecurityHigh
Red Hat Security Advisory: squid security update
- +1 more
Patch Availability(11)
| Vendor / Ecosystem | Fix (by version range) / Patch | Released | Source |
|---|---|---|---|
| ubuntu | squidclient (6.1-2ubuntu1.1) @ mantic | 2026-10-20 | ubuntu |
| ubuntu | squid3 (3.5.12-1ubuntu7.16+esm2) @ xenial | 2026-10-20 | ubuntu |
| redhat | squid-7:3.5.20-17.el7_9.10 | 2024-04-11 | redhat |
| redhat | squid-7:5.2-1.el9_0.4 | 2024-03-05 | redhat |
| redhat | squid:4-8020020240122164331.4cda2c84 | 2024-02-12 | redhat |
| redhat | squid:4-8040020240122165847.522a0ee4 | 2024-02-12 | redhat |
| redhat | squid:4-8060020231222131040.ad008a3a | 2024-02-12 | redhat |
| redhat | squid:4-8080020231222130009.63b34585 | 2024-01-24 | redhat |
| redhat | squid-7:5.5-6.el9_3.5 | 2024-01-08 | redhat |
| redhat | squid-7:5.5-5.el9_2.3 | 2024-01-08 | redhat |
| redhat | squid:4-8090020231207155957.a75119d5 | 2024-01-03 | redhat |
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
(4 across 4 ecosystems)
Debian:11(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| squid | 4.13-10, 4.13-10+deb11u1, 4.13-10+deb11u2, 4.13-10+deb11u3, 4.13-10+deb11u4 |
| — |
Debian:12(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| squid | 5.7-2, 5.7-2+deb12u1, 5.7-2+deb12u2, 5.7-2+deb12u3, 5.7-2+deb12u4 |
| — |
Debian:13(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| squid | — |
| — |
Debian:14(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| squid | — |
| — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Additional Vendor Advisories
(2)
Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.
Data Freshness Timeline
(refreshed 9× in last 7d / 32× 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 90 of 193 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. 10 repeat rows among the latest 100 are merged into the row they repeat. The 103 oldest rows on record are not shown and were not checked, so the counts can still include repeats.
- 2026-10-22 16:31 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-10-21 16:29 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-10-20 21:59 UTCEG score recompute
- 2026-10-20 21:59 UTCVendor advisory
- 2026-10-20 16:30 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-10-19 16:29 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-10-18 07:47 UTCEG score recompute
- 2026-10-17 16:30 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-10-16 16:36 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-10-15 16:29 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-10-14 16:30 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-10-13 16:30 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-10-12 18:24 UTCOSV refresh
- 2026-10-12 18:17 UTCEG score recompute
- 2026-10-12 16:31 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-10-11 21:42 UTCEG score recompute
- 2026-10-11 13:45 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-10-10 19:57 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-10-09 20:05 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-10-08 17:06 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-10-07 23:46 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-10-06 15:15 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-10-05 17:41 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-10-03 14:23 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-10-01 19:48 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
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- 2026-09-30 16:32 UTCEG score recompute
- 2026-09-30 15:01 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-09-29 15:17 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-09-28 13:49 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-09-27 13:42 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-09-26 00:22 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-09-24 14:01 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-09-23 13:46 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-09-22 17:38 UTCOSV refresh
- 2026-09-22 14:46 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-09-21 20:31 UTCEPSS rescoreEPSS 6.0% · 93rd percentile
- 2026-09-20 20:14 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-09-18 19:26 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-09-17 19:25 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-09-16 14:06 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-09-16 05:11 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-09-15 03:08 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-09-13 16:44 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-09-12 14:58 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-09-11 14:50 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-09-11 09:34 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-09-08 21:58 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-09-06 13:45 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-09-05 15:26 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-09-04 13:58 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-09-04 05:04 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-09-03 13:46 UTCOSV refresh
- 2026-09-02 14:09 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-09-01 13:51 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-09-01 04:35 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-30 19:15 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-30 01:20 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-28 21:39 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-27 14:23 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-26 14:44 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-25 13:46 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-24 14:14 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-23 00:17 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-21 23:47 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-20 22:53 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-19 17:02 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-18 13:46 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-17 03:18 UTCOSV refresh
- 2026-08-16 14:54 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-16 02:12 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-15 01:28 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-13 21:58 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-12 13:49 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-11 13:40 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-09 13:44 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-08 16:35 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-07 16:25 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-06 13:45 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-05 19:15 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-04 15:07 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-04 10:35 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-03 10:34 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-02 02:25 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-08-01 21:36 UTCOSV refresh
- 2026-08-01 04:14 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-07-30 16:26 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-07-30 01:28 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-07-28 15:34 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-07-27 14:10 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
- 2026-07-25 14:16 UTCEPSS rescoreEPSS 6.0% · 92nd percentile
Related CVEs(same product + same vendor + same CWE)
Same product
10 shownDebian:11:squid
- CVE-2005-0194EG 10.0EPSS p92HIGH
- CVE-2004-0541EG 10.0EPSS p99HIGH
- CVE-2020-15049EG 9.9EPSS p93CRITICAL
- CVE-2025-21311EG 9.8CRITICAL
- CVE-2020-11945EG 9.8EPSS p98CRITICAL
- CVE-2019-12519EG 9.8EPSS p94CRITICAL
- CVE-2019-12524EG 9.8EPSS p90CRITICAL
- CVE-2019-12526EG 9.8EPSS p97CRITICAL
- CVE-2019-12525EG 9.8EPSS p98CRITICAL
- CVE-2025-54574EG 9.3EPSS p98CRITICAL
Same vendor
10 shownredhat:RHSA-2024:0046 · redhat:RHSA-2024:0072 · redhat:RHSA-2024:0397
- CVE-2023-46724EG 7.5EPSS p91HIGH
- CVE-2023-49285NVD 7.5EG 9.0EPSS p100CRITICAL
- CVE-2023-49286EG 7.5EPSS p96HIGH
- CVE-2025-54574EG 9.3EPSS p98CRITICAL
- CVE-2023-50269NVD 7.5EG 8.3EPSS p99HIGH
- CVE-2023-5824EG 7.5HIGH
- CVE-2023-46847NVD 7.5EG 8.8EPSS p100HIGH
- CVE-2024-25617NVD 5.3EG 9.0EPSS p100CRITICAL
- CVE-2023-46848EG 7.5EPSS p96HIGH
- CVE-2023-46846EG 5.3EPSS p94MEDIUM
Frequently asked(5)
What is CVE-2023-46728?
When was the CVE record for CVE-2023-46728 published?
Is CVE-2023-46728 actively exploited?
What is the CVSS score of CVE-2023-46728?
How do I remediate CVE-2023-46728?
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2023-46728
Is Your Infrastructure Affected by CVE-2023-46728?
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