NGINX before 1.13.6 has a buffer overflow for years that exceed four digits, as demonstrated by a file with a modification date in 1969 that
NGINX before 1.13.6 has a buffer overflow for years that exceed four digits, as demonstrated by a file with a modification date in 1969 that causes an integer overflow (or a false modification date far in the future), when encountered by the autoindex module.
- Published
- Jun 6, 2021
- Updated
- Jun 16, 2026
- EPSS
- 3.3% · 88th percentile
- CWE
- CWE-190
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Report tools
Action score
40
Plan
Add it to your regular patch cycle.
- CVSS
- 39 / 40 · 9.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 3.3%
CISA SSVC decision
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
Vulnrichment: CISA's decision-tree inputs.
Affected systems
Using nginx? Add it to your stack and be the first to know about CVEs like this one. (Nginx)
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- f5 nginxbefore 1.13.6
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | nginx | before 1.13.6-1 | 1.13.6-1 |
| Debian:9 | nginx | before 1.10.3-1+deb9u7 | 1.10.3-1+deb9u7 |
Same product
f5: all recordsOther highest-scoring records for the same primary product.
- CVE-2013-2028The ngx_http_parse_chunked function in http/ngx_http_parse.c in nginx 1.3.9 through 1.4.0 allows remote attackers to cause a denial of servi56Plan
- CVE-2016-0742The resolver in nginx before 1.8.1 and 1.9.x before 1.9.10 allows remote attackers to cause a denial of service (invalid pointer dereference55Plan
- CVE-2009-2629Buffer underflow in src/http/ngx_http_parse.c in nginx 0.1.0 through 0.5.37, 0.6.x before 0.6.39, 0.7.x before 0.7.62, and 0.8.x before 0.8.53Plan
- CVE-2013-4547nginx 0.8.41 through 1.4.3 and 1.5.x before 1.5.7 allows remote attackers to bypass intended restrictions via an unescaped space character i50Plan
- CVE-2017-7529Nginx versions since 0.5.6 up to and including 1.13.2 are vulnerable to integer overflow vulnerability in nginx range filter module resultin49Plan
- CVE-2021-23017A security issue in nginx resolver was identified, which might allow an attacker who is able to forge UDP packets from the DNS server to cau46Plan
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 |
|---|---|---|
| debian:nginx | 1.13.6-1 · Debian:12 | 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
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-190 · Integer Overflow or WraparoundCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvd-primary
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)
ATT&CK techniques
—
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for all 385,000+ vulnerabilities; 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 helpChange log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- nginx.org/en/CHANGES
- github.com/nginx/nginx/commit/0206ebe76f748bb39d9de4dd4b3fce777fdfdccf
- github.com/nginx/nginx/commit/b900cc28fcbb4cf5a32ab62f80b59292e1c85b4b
- lists.debian.org/debian-lts-announce/2021/06/msg00009.html
- security.netapp.com/advisory/ntap-20210805-0006/
Vendor advisories and official records. Exploit/PoC links are deliberately left out.