CVE-2021-47958

MEDIUMNVD 4.34.3—
EchelonGraph scoreMEDIUM confidence

Score 4.3 from GitHub Security Advisory published 2026-05-15. NVD baseline CVSS 4.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Elevated
4.3
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 4.3Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

CouchCMS 2.2.1 contains a server-side request forgery vulnerability that allows authenticated attackers to make arbitrary HTTP requests by uploading malicious SVG files. Attackers can upload SVG files containing external entity references through the browse.php endpoint to access internal services and resources.

CVSS v3
4.3
EG Score
4.3(medium)
EPSS
14.8%
KEV
Not listed

Published

May 15, 2026

Last Modified

May 18, 2026

Advisory Details (3)

Auto-updated Jun 26, 2026
🔬 Proof of concept available. No patch confirmed yet.
generic

CouchCMS 2.2.1 Server-Side Request Forgery via SVG upload | Advisories | VulnCheck

https://www.vulncheck.com/advisories/couchcms-server-side-request-forgery-via-svg-upload
generic🟡 PoC Available

CouchCMS 2.2.1 - Server-Side Request Forgery - PHP webapps Exploit

https://www.exploit-db.com/exploits/49675
generic

GitHub - CouchCMS/CouchCMS: Simple Open-Source CMS for designers · GitHub

https://github.com/CouchCMS/CouchCMS

Vendor Advisories for CVE-2021-47958(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 11× in last 7d / 67× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. 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. Most recent first.

Showing the most recent 100 of 161 total refreshes for this CVE.

  1. 2026-07-12 05:44 UTCEPSS rescore
  2. 2026-07-11 08:25 UTCEPSS rescore
  3. 2026-07-09 19:07 UTCEPSS rescore
  4. 2026-07-09 19:07 UTCEPSS rescore
  5. 2026-07-08 15:12 UTCEPSS rescore
  6. 2026-07-08 15:12 UTCEPSS rescore
  7. 2026-07-07 13:43 UTCEPSS rescore
  8. 2026-07-06 16:25 UTCEPSS rescore
  9. 2026-07-06 16:25 UTCEPSS rescore
  10. 2026-07-06 02:21 UTCEPSS rescore
  11. 2026-07-06 02:21 UTCEPSS rescore
  12. 2026-07-05 02:28 UTCEPSS rescore
  13. 2026-07-05 02:28 UTCEPSS rescore
  14. 2026-07-04 06:29 UTCEPSS rescore
  15. 2026-07-04 06:29 UTCEPSS rescore
  16. 2026-07-01 15:04 UTCEPSS rescore
  17. 2026-06-30 23:20 UTCEPSS rescore
  18. 2026-06-29 21:27 UTCEG score recompute
  19. 2026-06-29 21:27 UTCGHSA enrichment
  20. 2026-06-29 14:04 UTCEPSS rescore
  21. 2026-06-29 14:04 UTCEPSS rescore
  22. 2026-06-28 14:05 UTCEPSS rescore
  23. 2026-06-28 04:54 UTCEPSS rescore
  24. 2026-06-28 04:54 UTCEPSS rescore
  25. 2026-06-27 21:51 UTCEG score recompute
Show 75 more
  1. 2026-06-27 21:51 UTCGHSA enrichment
  2. 2026-06-27 03:07 UTCEPSS rescore
  3. 2026-06-27 03:06 UTCEPSS rescore
  4. 2026-06-26 20:11 UTCEG score recompute
  5. 2026-06-26 20:11 UTCGHSA enrichment
  6. 2026-06-25 18:44 UTCEG score recompute
  7. 2026-06-25 18:44 UTCGHSA enrichment
  8. 2026-06-25 13:48 UTCEPSS rescore
  9. 2026-06-25 13:48 UTCEPSS rescore
  10. 2026-06-24 14:03 UTCEPSS rescore
  11. 2026-06-24 14:03 UTCEPSS rescore
  12. 2026-06-23 21:31 UTCEPSS rescore
  13. 2026-06-23 21:31 UTCEPSS rescore
  14. 2026-06-22 14:24 UTCEPSS rescore
  15. 2026-06-21 14:55 UTCEPSS rescore
  16. 2026-06-21 01:58 UTCEPSS rescore
  17. 2026-06-21 01:58 UTCEPSS rescore
  18. 2026-06-19 19:24 UTCEPSS rescore
  19. 2026-06-19 19:24 UTCEPSS rescore
  20. 2026-06-18 17:51 UTCEPSS rescore
  21. 2026-06-18 17:51 UTCEPSS rescore
  22. 2026-06-17 21:47 UTCEG score recompute
  23. 2026-06-17 21:47 UTCGHSA enrichment
  24. 2026-06-17 17:51 UTCEPSS rescore
  25. 2026-06-17 17:51 UTCEPSS rescore
  26. 2026-06-16 22:43 UTCEG score recompute
  27. 2026-06-16 22:43 UTCGHSA enrichment
  28. 2026-06-16 17:51 UTCEPSS rescore
  29. 2026-06-15 23:32 UTCEG score recompute
  30. 2026-06-15 23:32 UTCGHSA enrichment
  31. 2026-06-15 17:46 UTCEPSS rescore
  32. 2026-06-14 23:15 UTCEPSS rescore
  33. 2026-06-14 23:15 UTCEPSS rescore
  34. 2026-06-14 22:21 UTCEG score recompute
  35. 2026-06-14 22:21 UTCGHSA enrichment
  36. 2026-06-13 23:16 UTCEG score recompute
  37. 2026-06-13 23:16 UTCGHSA enrichment
  38. 2026-06-13 22:58 UTCEPSS rescore
  39. 2026-06-13 22:58 UTCEPSS rescore
  40. 2026-06-12 23:10 UTCEPSS rescore
  41. 2026-06-12 19:00 UTCEG score recompute
  42. 2026-06-12 18:59 UTCGHSA enrichment
  43. 2026-06-11 19:55 UTCEG score recompute
  44. 2026-06-11 19:55 UTCGHSA enrichment
  45. 2026-06-11 13:58 UTCEPSS rescore
  46. 2026-06-10 22:16 UTCEPSS rescore
  47. 2026-06-10 20:52 UTCEG score recompute
  48. 2026-06-10 20:52 UTCGHSA enrichment
  49. 2026-06-10 13:20 UTCEPSS rescore
  50. 2026-06-09 21:39 UTCEG score recompute
  51. 2026-06-09 21:39 UTCGHSA enrichment
  52. 2026-06-08 22:01 UTCEG score recompute
  53. 2026-06-08 22:01 UTCGHSA enrichment
  54. 2026-06-08 14:15 UTCEPSS rescore
  55. 2026-06-08 14:15 UTCEPSS rescore
  56. 2026-06-08 14:15 UTCEPSS rescore
  57. 2026-06-07 22:58 UTCEG score recompute
  58. 2026-06-07 22:58 UTCGHSA enrichment
  59. 2026-06-07 15:23 UTCEPSS rescore
  60. 2026-06-07 15:23 UTCEPSS rescore
  61. 2026-06-06 23:55 UTCEG score recompute
  62. 2026-06-06 23:55 UTCGHSA enrichment
  63. 2026-06-06 13:46 UTCEPSS rescore
  64. 2026-06-06 13:46 UTCEPSS rescore
  65. 2026-06-06 00:51 UTCEG score recompute
  66. 2026-06-06 00:51 UTCGHSA enrichment
  67. 2026-06-05 22:45 UTCEPSS rescore
  68. 2026-06-05 22:45 UTCEPSS rescore
  69. 2026-06-05 06:09 UTCEPSS rescore
  70. 2026-06-05 06:09 UTCEPSS rescore
  71. 2026-06-05 01:48 UTCEG score recompute
  72. 2026-06-05 01:48 UTCGHSA enrichment
  73. 2026-06-04 13:11 UTCEPSS rescore
  74. 2026-06-04 13:10 UTCEPSS rescore
  75. 2026-06-04 02:44 UTCEG score recompute

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2021-47958?
CVE-2021-47958 is a medium vulnerability published on May 15, 2026. CouchCMS 2.2.1 contains a server-side request forgery vulnerability that allows authenticated attackers to make arbitrary HTTP requests by uploading malicious SVG files. Attackers can upload SVG files containing external entity references through the browse.php endpoint to access internal services…
When was CVE-2021-47958 disclosed?
CVE-2021-47958 was first published in the National Vulnerability Database on May 15, 2026, with the most recent update on May 18, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-47958 actively exploited?
CVE-2021-47958 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 14.8% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2021-47958?
CVE-2021-47958 has a CVSS v3 base score of 4.3 (NVD).
How do I remediate CVE-2021-47958?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-47958, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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