CVE-2013-4547

HIGHCVSS v2 · 7.57.5—
EchelonGraph scoreLOW confidence

This CVE was only ever scored under CVSS v2.0. NVD CVSS v2.0 base 7.5 — v2 rates that HIGH (v2 bands: LOW 0.0–3.9 / MEDIUM 4.0–6.9 / HIGH 7.0–10.0; v2 has no CRITICAL band). Vector AV:N/AC:L/Au:N/C:P/I:P/A:P. CVSS v2 is an older, coarser metric than v3.1/v4.0 (no Scope, no User Interaction, no Attack Requirements), so it is not directly comparable to a v3 or v4 score. NVD has never re-scored this record under v3. EPSS predicts 67.7% exploitation probability in the next 30 days, which is reflected in EG Risk but does not lift the v2 base. Confidence: LOW.

Triggered by: NVD CVSS v2.0 (legacy fallback)
Sources: epss, nvd_v2
Weaponized
7.5EG
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).
  • 11 internet-facing services (distinct ip:port) on record running an affected version — derived from Shodan data (© Shodan); a patched service can stay counted while its port stays open
  • High exploitation likelihood — EPSS 68%
  • Public exploit code is available (Exploit-DB, marked verified by Exploit-DB, other public proof-of-concept code)
CISA-KEV: Not listedEPSS PROB: 68%CVSS v2: 7.5Exploit: Exploit-DB (verified) · other public PoCExposed services: 11

A fix is available — apply it.

nginx 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 in a URI.

Internet exposure · derived from Shodan data

11 internet-facing services (distinct ip:port) on record running a version that maps to CVE-2013-4547, in our KEV-Exposure radar’s Shodan-derived sample.

across 8 countries (Italy, Japan, United States, Germany, Indonesia)top: nginx
See the KEV-Exposure radar →Derived from Shodan data. Shodan data is owned by Shodan, which holds its copyright (© Shodan). EchelonGraph claims no ownership of it or copyright in it. Aggregate, host-redacted.

How it counts: every 12 hours, when Shodan query credits allow, the radar runs one Shodan query per tracked product, reads up to 100 ip:port services per query, and keeps a service when its banner version matches a CISA-KEV or high-EPSS CVE; a service is dropped when neither a search nor a Shodan InternetDB port re-check has refreshed it for 21 days. A re-check that finds the port still listed by Shodan InternetDB refreshes the service without re-reading the banner, so a patched service can stay counted while its port stays open. A count is a banner-version inference over a sample, not an exploit test and not an internet-wide census, and the unit is a service, not a machine: a machine answering on two ports counts twice.

CVSS v2.0 (legacy)
7.5HIGHNVD never assigned a CVSS v3 rating to this CVE
EG Score
7.5HIGHlow confidence
EG Risk
65
EG Risk 65/100

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)
Severity75% × 45%
The EG Score, 7.5 of 10.
Exploitation68% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability30% × 15%
EchelonGraph's default before algorithm v3.4: CISA had not published Automatable for this CVE.
SSVC (CISA's decision table, applied by EchelonGraph): Track at low, Track or Track* at medium and Track* or Attend at high mission impact.
Exploitation public PoC (EG-KEV: weaponized) · Automatable unknown (not published for this CVE) · Technical impact unknown (not published for this CVE). EchelonGraph holds no SSVC assessment of this CVE from CISA: none of these inputs is from 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
68%
EPSS %ILE
99th
KEV
Not listed

SSVC (CISA's decision table, applied by EchelonGraph)Track at low, Track or Track* at medium and Track* or Attend at high mission impact.

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation public PoC (EG-KEV: weaponized) · Automatable unknown (not published for this CVE) · Technical impact unknown (not published for this CVE). EchelonGraph holds no SSVC assessment of this CVE from CISA: none of these inputs is from 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

Published

November 23, 2013

Last Modified

April 29, 2026

References (9)

Affected Packages

(5 across 5 ecosystems)
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
nginx—
  • every version up to 1.4.4-1: fixed in 1.4.4-1
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
nginx—
  • every version up to 1.4.4-1: fixed in 1.4.4-1
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
nginx—
  • every version up to 1.4.4-1: fixed in 1.4.4-1
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
nginx—
  • every version up to 1.4.4-1: fixed in 1.4.4-1
—
Debian:7(1)
PackageVulnerable rangeFix by version rangeDependents
nginx1.2.1-2.2, 1.2.1-2.2+wheezy1
  • every version up to 1.2.1-2.2+wheezy2: fixed in 1.2.1-2.2+wheezy2
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 5× in last 7d / 17× 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 83 of 86 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. 17 repeat rows among the latest 100 are merged into the row they repeat. The 3 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-11 13:39 UTCEPSS rescoreEPSS 68% · 99th percentile
  2. 2026-10-09 20:01 UTCEPSS rescoreEPSS 68% · 99th percentile
  3. 2026-10-08 16:34 UTCEPSS rescoreEPSS 68% · 99th percentile
  4. 2026-10-07 23:39 UTCEPSS rescoreEPSS 68% · 99th percentile
  5. 2026-10-06 15:11 UTCEPSS rescoreEPSS 68% · 99th percentile
  6. 2026-09-30 14:58 UTCEPSS rescoreEPSS 68% · 99th percentile
  7. 2026-09-30 01:09 UTCOSV refresh
  8. 2026-09-30 00:13 UTCEG score recompute
  9. 2026-09-27 13:39 UTCEPSS rescoreEPSS 68% · 99th percentile
  10. 2026-09-26 15:53 UTCEPSS rescoreEPSS 68% · 99th percentile
  11. 2026-09-21 20:25 UTCEPSS rescoreEPSS 68% · 99th percentile
  12. 2026-09-20 20:08 UTCEPSS rescoreEPSS 68% · 99th percentile
  13. 2026-09-18 19:21 UTCEPSS rescoreEPSS 68% · 99th percentile
  14. 2026-09-17 19:21 UTCEPSS rescoreEPSS 68% · 99th percentile
  15. 2026-09-15 03:04 UTCEPSS rescoreEPSS 68% · 99th percentile
  16. 2026-09-13 16:41 UTCEPSS rescoreEPSS 68% · 99th percentile
  17. 2026-09-12 14:55 UTCEPSS rescoreEPSS 68% · 99th percentile
  18. 2026-09-11 09:30 UTCEPSS rescoreEPSS 68% · 99th percentile
  19. 2026-09-11 00:23 UTCOSV refresh
  20. 2026-09-04 13:55 UTCEPSS rescoreEPSS 68% · 99th percentile
  21. 2026-08-30 19:12 UTCEPSS rescoreEPSS 68% · 99th percentile
  22. 2026-08-26 14:41 UTCEPSS rescoreEPSS 68% · 99th percentile
  23. 2026-08-23 15:52 UTCOSV refresh
  24. 2026-08-21 23:44 UTCEPSS rescoreEPSS 68% · 99th percentile
  25. 2026-08-20 22:50 UTCEPSS rescoreEPSS 68% · 99th percentile
Show 58 more
  1. 2026-08-19 16:59 UTCEPSS rescoreEPSS 68% · 99th percentile
  2. 2026-08-16 02:09 UTCEPSS rescoreEPSS 68% · 99th percentile
  3. 2026-08-07 16:49 UTCOSV refresh
  4. 2026-08-07 16:21 UTCEPSS rescoreEPSS 68% · 99th percentile
  5. 2026-08-06 13:42 UTCEPSS rescoreEPSS 68% · 99th percentile
  6. 2026-08-05 19:12 UTCEPSS rescoreEPSS 68% · 99th percentile
  7. 2026-07-30 16:23 UTCEPSS rescoreEPSS 68% · 99th percentile
  8. 2026-07-30 01:26 UTCEPSS rescoreEPSS 68% · 99th percentile
  9. 2026-07-28 15:31 UTCEPSS rescoreEPSS 68% · 99th percentile
  10. 2026-07-26 13:48 UTCEG score recompute▲ 7.50
  11. 2026-07-23 01:10 UTCEG score recompute▼ 6.20
  12. 2026-07-23 00:14 UTCEG score recompute▲ 6.20
  13. 2026-07-22 21:52 UTCEG score recompute▼ 9.00
  14. 2026-07-22 14:04 UTCEPSS rescoreEPSS 68% · 99th percentile
  15. 2026-07-22 09:37 UTCOSV refresh
  16. 2026-07-21 15:21 UTCEPSS rescoreEPSS 68% · 99th percentile
  17. 2026-07-20 17:03 UTCEPSS rescoreEPSS 68% · 99th percentile
  18. 2026-07-19 02:25 UTCEPSS rescoreEPSS 68% · 99th percentile
  19. 2026-07-16 16:58 UTCEPSS rescoreEPSS 68% · 99th percentile
  20. 2026-07-15 16:54 UTCEPSS rescoreEPSS 68% · 99th percentile
  21. 2026-07-13 22:26 UTCEPSS rescoreEPSS 68% · 99th percentile
  22. 2026-07-13 06:08 UTCEPSS rescoreEPSS 68% · 99th percentile
  23. 2026-07-12 05:42 UTCEPSS rescoreEPSS 68% · 99th percentile
  24. 2026-07-09 19:05 UTCEPSS rescoreEPSS 68% · 99th percentile
  25. 2026-07-08 15:10 UTCEPSS rescoreEPSS 68% · 99th percentile
  26. 2026-07-07 13:41 UTCEPSS rescoreEPSS 68% · 99th percentile
  27. 2026-07-05 04:51 UTCOSV refresh
  28. 2026-07-05 02:26 UTCEPSS rescoreEPSS 68% · 99th percentile
  29. 2026-07-02 15:21 UTCEPSS rescoreEPSS 68% · 99th percentile
  30. 2026-07-01 15:02 UTCEPSS rescoreEPSS 68% · 99th percentile
  31. 2026-06-30 23:19 UTCEPSS rescoreEPSS 68% · 99th percentile
  32. 2026-06-29 14:02 UTCEPSS rescoreEPSS 68% · 99th percentile
  33. 2026-06-28 14:03 UTCEPSS rescoreEPSS 68% · 99th percentile
  34. 2026-06-27 03:05 UTCEPSS rescoreEPSS 68% · 99th percentile
  35. 2026-06-25 13:47 UTCEPSS rescoreEPSS 68% · 99th percentile
  36. 2026-06-24 14:02 UTCEPSS rescoreEPSS 68% · 99th percentile
  37. 2026-06-23 21:30 UTCEPSS rescoreEPSS 68% · 99th percentile
  38. 2026-06-18 17:49 UTCEPSS rescoreEPSS 68% · 99th percentile
  39. 2026-06-17 17:49 UTCEPSS rescoreEPSS 68% · 99th percentile
  40. 2026-06-16 17:49 UTCEPSS rescoreEPSS 68% · 99th percentile
  41. 2026-06-16 16:09 UTCOSV refresh
  42. 2026-06-15 17:44 UTCEPSS rescoreEPSS 68% · 99th percentile
  43. 2026-06-14 23:14 UTCEPSS rescoreEPSS 91% · 99th percentile
  44. 2026-06-13 22:57 UTCEPSS rescoreEPSS 91% · 99th percentile
  45. 2026-06-12 23:08 UTCEPSS rescoreEPSS 91% · 99th percentile
  46. 2026-06-10 22:15 UTCEPSS rescoreEPSS 91% · 99th percentile
  47. 2026-06-10 13:18 UTCEPSS rescoreEPSS 91% · 99th percentile
  48. 2026-06-08 14:14 UTCEPSS rescoreEPSS 91% · 99th percentile
  49. 2026-06-07 15:22 UTCEPSS rescoreEPSS 91% · 99th percentile
  50. 2026-06-05 22:44 UTCEPSS rescoreEPSS 91% · 99th percentile
  51. 2026-06-05 06:08 UTCEPSS rescoreEPSS 91% · 99th percentile
  52. 2026-06-04 13:09 UTCEPSS rescoreEPSS 91% · 99th percentile
  53. 2026-05-31 00:14 UTCEPSS rescoreEPSS 91% · 99th percentile
  54. 2026-05-28 21:30 UTCEG score recompute
  55. 2026-05-28 21:30 UTCGHSA enrichmentGHSA-9x2q-qf8w-h347 · GitHub severity HIGH
  56. 2026-05-27 13:38 UTCEPSS rescoreEPSS 91% · 99th percentile
  57. 2026-05-26 13:41 UTCEPSS rescoreEPSS 91% · 99th percentile
  58. 2026-05-26 07:16 UTCEPSS rescoreEPSS 91% · 99th percentile

Publicly available exploits

(2 references)

Public exploit code is referenced for this CVE (1 Exploit-DB entry, 1 GitHub PoC). Defenders should treat patch urgency accordingly.

  • Exploit-DBEDB-38846✓ verified
    Published Nov 19, 2013

    Nginx 1.1.17 - URI Processing SecURIty Bypass

    Open source ↗
  • GitHub PoCcyberharsh/Nginx-CVE-2013-4547
    Published Jun 20, 2020
    Open source ↗

Related CVEs(same product + same CWE)

Frequently asked(4)

What is CVE-2013-4547?
CVE-2013-4547 is a high-severity vulnerability; its CVE record was published on November 23, 2013. nginx 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 in a URI.
When was the CVE record for CVE-2013-4547 published?
The CVE record for CVE-2013-4547 was published on November 23, 2013. 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 April 29, 2026; the record at its source may have been updated since.
Is CVE-2013-4547 actively exploited?
CVE-2013-4547 is not currently on CISA's Known Exploited Vulnerabilities catalog. EchelonGraph's EG-KEV model places it in Tier 2 (Weaponized), which is not evidence of exploitation: Exploit-DB marks a public exploit for it as verified. EchelonGraph does not test whether exploit code works. FIRST EPSS estimates a 68% probability of exploitation in the next 30 days (99th percentile of EPSS-scored CVEs).
How do I remediate CVE-2013-4547?
A fix for CVE-2013-4547 is available: update to the fixed version the vendor names in its advisory.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2013-4547

Explore →

Is Your Infrastructure Affected by CVE-2013-4547?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Book a Demo →Browse All CVEs