An issue was discovered in Squid 2.x, 3.x, and 4.x through 4.8.
An issue was discovered in Squid 2.x, 3.x, and 4.x through 4.8. Due to incorrect data management, it is vulnerable to information disclosure when processing HTTP Digest Authentication. Nonce tokens contain the raw byte value of a pointer that sits within heap memory allocation. This information reduces ASLR protections and may aid attackers isolating memory areas to target for remote code execution attacks.
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for help- Published
- Nov 26, 2019
- Updated
- Jun 16, 2026
- EPSS
- 41.0% · 99th percentile
- CWE
- CWE-200
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Report tools
Action score
42
Plan
Add it to your regular patch cycle.
- CVSS
- 30 / 40 · 7.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 12 / 30 · 41.0%
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| squid-cache | squid | cpe:2.3:a:squid-cache:squid |
| canonical | ubuntu linux | cpe:2.3:o:canonical:ubuntu_linux |
| debian | debian linux | cpe:2.3:o:debian:debian_linux |
| fedoraproject | fedora | cpe:2.3:o:fedoraproject:fedora |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- canonical ubuntu linux16.04
- canonical ubuntu linux18.04
- canonical ubuntu linux19.04
- canonical ubuntu linux19.10
- debian debian linux8.0
- fedoraproject fedora30
- fedoraproject fedora31
- squid-cache squid4.0 and later · up to 4.8 inclusive
- squid-cache squid3.0 and later · up to 3.5.28 inclusive
- squid-cache squid2.0 and later · up to 2.7 inclusive
- squid-cache squid2.7
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| AlmaLinux:8 | libecap | before 1.0.1-2.module_el8.6.0+2741+01592ae8 | 1.0.1-2.module_el8.6.0+2741+01592ae8 |
| AlmaLinux:8 | libecap-devel | before 1.0.1-2.module_el8.6.0+2741+01592ae8 | 1.0.1-2.module_el8.6.0+2741+01592ae8 |
| Alpine:v3.10 | squid | from 2.0 · before 4.8-r1 | 4.8-r1 |
| Alpine:v3.11 | squid | from 2.0 · before 4.9-r0 | 4.9-r0 |
| Debian:10 | squid | before 4.6-1+deb10u2 | 4.6-1+deb10u2 |
| Debian:12 | squid | before 4.9-1 | 4.9-1 |
| Debian:8 | squid3 | before 3.4.8-6+deb8u9 | 3.4.8-6+deb8u9 |
| Debian:9 | squid3 | before 3.5.23-5+deb9u2 | 3.5.23-5+deb9u2 |
| openSUSE:Leap 15.0 | squid | before 4.9-lp150.13.1 | 4.9-lp150.13.1 |
| openSUSE:Leap 15.1 | squid | before 4.9-lp151.2.7.1 | 4.9-lp151.2.7.1 |
| Red Hat:enterprise_linux:8::appstream | libecap | before 0:1.0.1-2.module+el8.1.0+4044+36416a77 | 0:1.0.1-2.module+el8.1.0+4044+36416a77 |
| Red Hat:enterprise_linux:8::appstream | libecap-debuginfo | before 0:1.0.1-2.module+el8.1.0+4044+36416a77 | 0:1.0.1-2.module+el8.1.0+4044+36416a77 |
| Red Hat:enterprise_linux:8::appstream | libecap-debugsource | before 0:1.0.1-2.module+el8.1.0+4044+36416a77 | 0:1.0.1-2.module+el8.1.0+4044+36416a77 |
| Red Hat:enterprise_linux:8::appstream | libecap-devel | before 0:1.0.1-2.module+el8.1.0+4044+36416a77 | 0:1.0.1-2.module+el8.1.0+4044+36416a77 |
| Red Hat:enterprise_linux:8::appstream | squid | before 7:4.11-3.module+el8.3.0+7851+7808b5f9 | 7:4.11-3.module+el8.3.0+7851+7808b5f9 |
| Red Hat:enterprise_linux:8::appstream | squid-debuginfo | before 7:4.11-3.module+el8.3.0+7851+7808b5f9 | 7:4.11-3.module+el8.3.0+7851+7808b5f9 |
| Red Hat:enterprise_linux:8::appstream | squid-debugsource | before 7:4.11-3.module+el8.3.0+7851+7808b5f9 | 7:4.11-3.module+el8.3.0+7851+7808b5f9 |
| Rocky Linux:8 | libecap | before 0:1.0.1-2.module+el8.4.0+404+316a0dc5 | 0:1.0.1-2.module+el8.4.0+404+316a0dc5 |
| SUSE:HPE Helion OpenStack 8 | squid | before 3.5.21-26.20.1 | 3.5.21-26.20.1 |
| SUSE:Linux Enterprise Module for Server Applications 15 | squid | before 4.9-5.11.1 | 4.9-5.11.1 |
| SUSE:Linux Enterprise Point of Sale 11 SP3 | squid3 | before 3.1.23-8.16.37.12.1 | 3.1.23-8.16.37.12.1 |
| SUSE:Linux Enterprise Server 12 SP5 | squid | before 4.9-4.3.2 | 4.9-4.3.2 |
Same product
squid-cache: all recordsOther highest-scoring records for the same primary product.
- CVE-2023-46847Squid: denial of service in http digest authentication57Plan
- CVE-2024-25617Denial of Service in HTTP Header parser in squid proxy56Plan
- CVE-2023-49285Denial of Service in HTTP Message Processing in Squid56Plan
- CVE-2021-31806An issue was discovered in Squid before 4.15 and 5.x before 5.0.6.55Plan
- CVE-2020-8450An issue was discovered in Squid before 4.10.51Plan
- CVE-2024-25111SQUID-2024:1 Denial of Service in HTTP Chunked Decoding50Plan
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| almalinux:libecap | 1.0.1-2.module_el8.6.0+2741+01592ae8 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:libecap-devel | 1.0.1-2.module_el8.6.0+2741+01592ae8 · AlmaLinux:8 | Package registry (OSV) |
| alpine:squid | 4.8-r1 · Alpine:v3.10 | Package registry (OSV) |
| debian:squid | 4.9-1 · Debian:12 | Package registry (OSV) |
| debian:squid3 | 3.4.8-6+deb8u9 · Debian:8 | Package registry (OSV) |
| opensuse:squid | 4.9-lp150.13.1 · openSUSE:Leap 15.0 | Package registry (OSV) |
| red hat:libecap | 0:1.0.1-2.module+el8.1.0+4044+36416a77 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:libecap-debuginfo | 0:1.0.1-2.module+el8.1.0+4044+36416a77 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:libecap-debugsource | 0:1.0.1-2.module+el8.1.0+4044+36416a77 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:libecap-devel | 0:1.0.1-2.module+el8.1.0+4044+36416a77 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:squid | 7:4.11-3.module+el8.3.0+7851+7808b5f9 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:squid-debuginfo | 7:4.11-3.module+el8.3.0+7851+7808b5f9 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:squid-debugsource | 7:4.11-3.module+el8.3.0+7851+7808b5f9 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| rocky linux:libecap | 0:1.0.1-2.module+el8.4.0+404+316a0dc5 · Rocky Linux:8 | Package registry (OSV) |
| suse:squid | 4.9-5.11.1 · SUSE:Linux Enterprise Module for Server Applications 15 | Package registry (OSV) |
| suse:squid3 | 3.1.23-8.16.37.12.1 · SUSE:Linux Enterprise Point of Sale 11 SP3 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- none
- Availability
- none
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- None
- Availability impact
- None
Weakness class (CWE)
CWE-200 · Exposure of Sensitive Information to an Unauthorized ActorCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
nvd-primary
Root cause
The extension requests broader permissions than its function needs and sends the data it collects out for purposes beyond its stated function.
The bug in code
The whole CWE-200 classA representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.
Vulnerable
{ "permissions": ["tabs", "<all_urls>"], "background": { "service_worker": "analytics.js" }}Fixed
{ "permissions": ["activeTab"], "host_permissions": ["https://yildiz.example/*"]}Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
- ExcavationCAPEC-116likelihood: High · Medium
- Subverting Environment Variable ValuesCAPEC-13likelihood: High · Very High
- FootprintingCAPEC-169likelihood: High · Very Low
- Exploiting Trust in ClientCAPEC-22likelihood: High · High
- FingerprintingCAPEC-224likelihood: High · Very Low
- ICMP Echo Request PingCAPEC-285likelihood: Medium · Low
- TCP SYN ScanCAPEC-287Low
- Enumerate Mail Exchange (MX) RecordsCAPEC-290Low
ATT&CK techniques
- System Service DiscoveryT1007
- System Network Configuration DiscoveryT1016
- Remote System DiscoveryT1018
- System Owner/User DiscoveryT1033
- Masquerading: Match Legitimate Name or LocationT1036.005
- Network Service ScanningT1046
- System Network Connections DiscoveryT1049
- Process DiscoveryT1057
- Permission Groups DiscoveryT1069
- System Information DiscoveryT1082
- File and Directory DiscoveryT1083
- Account DiscoveryT1087
- Multi-Factor Authentication InterceptionT1111
- Peripheral Device DiscoveryT1120
- System Time DiscoveryT1124
- Access Token Manipulation:Token Impersonation/TheftT1134.001
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- www.squid-cache.org/Advisories/SQUID-2019_11.txt
- www.squid-cache.org/Versions/v4/changesets/squid-4-671ba97abe929156dc4c717ee52ad22fba0f7443.patch
- bugzilla.suse.com/show_bug.cgi?id=1156324
- github.com/squid-cache/squid/pull/491
- lists.debian.org/debian-lts-announce/2019/12/msg00011.html
- lists.debian.org/debian-lts-announce/2020/07/msg00009.html
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MTM74TU2BSLT5B3H4F3UDW53672NVLMC/
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UEMOYTMCCFWK5NOXSXEIH5D2VGWVXR67/
- security.gentoo.org/glsa/202003-34
- usn.ubuntu.com/4213-1/
- www.debian.org/security/2020/dsa-4682
Vendor advisories and official records. Exploit/PoC links are deliberately left out.