CVE-2021-44548

CRITICALNVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.8 under NVD CVSS v3. EPSS exploit probability: 5.0%, top 10% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
9.8
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 5%CVSS: 9.8Exploit: NoneExposed: 0

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

An Improper Input Validation vulnerability in DataImportHandler of Apache Solr allows an attacker to provide a Windows UNC path resulting in an SMB network call being made from the Solr host to another host on the network. If the attacker has wider access to the network, this may lead to SMB attacks, which may result in: * The exfiltration of sensitive data such as OS user hashes (NTLM/LM hashes), * In case of misconfigured systems, SMB Relay Attacks which can lead to user impersonation on SMB Shares or, in a worse-case scenario, Remote Code Execution This issue affects all Apache Solr versions prior to 8.11.1. This issue only affects Windows.

CVSS v3
9.8
EG Score
9.8(medium)
EPSS
91.3%
KEV
Not listed

Published

December 23, 2021

Last Modified

November 21, 2024

Advisory Details (2)

Auto-updated Jul 2, 2026
No patch confirmed yet.
generic

Solr™ Security - Apache Solr

https://solr.apache.org/security.html#cve-2021-44548-apache-solr-information-disclosure-vulnerability-through-dataimporthandler
generic

NetApp Product Security

https://security.netapp.com/advisory/ntap-20220114-0005/

Affected Packages

(1 across 1 ecosystem)
Maven(1)
PackageVulnerable rangeFixed inDependents
org.apache.solr:solr-parent1.3.0 ... 8.9.0 (106 versions)8.11.1—

Weakness Classification(3)

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

Data Freshness Timeline

(refreshed 10× in last 7d / 47× 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.

  1. 2026-07-11 08:25 UTCEPSS rescore
  2. 2026-07-11 08:25 UTCEPSS rescore
  3. 2026-07-09 19:07 UTCEPSS rescore
  4. 2026-07-08 15:12 UTCEPSS rescore
  5. 2026-07-06 16:25 UTCEPSS rescore
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  7. 2026-07-06 02:21 UTCEPSS rescore
  8. 2026-07-06 02:21 UTCEPSS rescore
  9. 2026-07-05 02:28 UTCEPSS rescore
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  11. 2026-07-04 06:29 UTCEPSS rescore
  12. 2026-07-04 06:29 UTCEPSS rescore
  13. 2026-07-02 16:57 UTCEPSS rescore
  14. 2026-07-01 15:04 UTCEPSS rescore
  15. 2026-06-30 23:20 UTCEPSS rescore
  16. 2026-06-30 23:20 UTCEPSS rescore
  17. 2026-06-30 00:30 UTCOSV refresh
  18. 2026-06-29 14:04 UTCEPSS rescore
  19. 2026-06-28 14:05 UTCEPSS rescore
  20. 2026-06-28 04:54 UTCEPSS rescore
  21. 2026-06-28 04:54 UTCEPSS rescore
  22. 2026-06-27 03:06 UTCEPSS rescore
  23. 2026-06-27 03:06 UTCEPSS rescore
  24. 2026-06-25 13:48 UTCEPSS rescore
  25. 2026-06-25 13:48 UTCEPSS rescore
Show 57 more
  1. 2026-06-24 14:03 UTCEPSS rescore
  2. 2026-06-24 14:03 UTCEPSS rescore
  3. 2026-06-23 21:31 UTCEPSS rescore
  4. 2026-06-23 21:31 UTCEPSS rescore
  5. 2026-06-22 14:24 UTCEPSS rescore
  6. 2026-06-21 14:55 UTCEPSS rescore
  7. 2026-06-21 01:58 UTCEPSS rescore
  8. 2026-06-21 01:58 UTCEPSS rescore
  9. 2026-06-18 17:51 UTCEPSS rescore
  10. 2026-06-18 17:51 UTCEPSS rescore
  11. 2026-06-17 17:51 UTCEPSS rescore
  12. 2026-06-17 17:51 UTCEPSS rescore
  13. 2026-06-17 17:51 UTCEPSS rescore
  14. 2026-06-16 17:51 UTCEPSS rescore
  15. 2026-06-16 17:51 UTCEPSS rescore
  16. 2026-06-15 17:46 UTCEPSS rescore
  17. 2026-06-14 23:15 UTCEPSS rescore
  18. 2026-06-14 23:15 UTCEPSS rescore
  19. 2026-06-13 22:58 UTCEPSS rescore
  20. 2026-06-13 22:58 UTCEPSS rescore
  21. 2026-06-12 23:10 UTCEPSS rescore
  22. 2026-06-12 13:40 UTCOSV refresh
  23. 2026-06-11 13:58 UTCEPSS rescore
  24. 2026-06-11 13:58 UTCEPSS rescore
  25. 2026-06-10 22:16 UTCEPSS rescore
  26. 2026-06-10 22:16 UTCEPSS rescore
  27. 2026-06-10 13:20 UTCEPSS rescore
  28. 2026-06-08 14:15 UTCEPSS rescore
  29. 2026-06-08 14:15 UTCEPSS rescore
  30. 2026-06-07 15:23 UTCEPSS rescore
  31. 2026-06-07 15:23 UTCEPSS rescore
  32. 2026-06-06 13:46 UTCEPSS rescore
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  34. 2026-06-05 22:45 UTCEPSS rescore
  35. 2026-06-05 06:09 UTCEPSS rescore
  36. 2026-06-05 06:09 UTCEPSS rescore
  37. 2026-06-04 13:10 UTCEPSS rescore
  38. 2026-06-04 13:10 UTCEPSS rescore
  39. 2026-06-02 20:11 UTCEPSS rescore
  40. 2026-06-02 20:11 UTCEPSS rescore
  41. 2026-06-01 13:50 UTCEPSS rescore
  42. 2026-06-01 13:50 UTCEPSS rescore
  43. 2026-05-31 22:29 UTCEPSS rescore
  44. 2026-05-31 22:29 UTCEPSS rescore
  45. 2026-05-31 00:15 UTCEPSS rescore
  46. 2026-05-31 00:15 UTCEPSS rescore
  47. 2026-05-29 13:42 UTCEPSS rescore
  48. 2026-05-28 13:43 UTCEPSS rescore
  49. 2026-05-28 13:43 UTCEPSS rescore
  50. 2026-05-27 13:39 UTCEPSS rescore
  51. 2026-05-27 13:39 UTCEPSS rescore
  52. 2026-05-26 13:42 UTCEPSS rescore
  53. 2026-05-26 13:42 UTCEPSS rescore
  54. 2026-05-26 07:17 UTCEPSS rescore
  55. 2026-05-26 07:17 UTCEPSS rescore
  56. 2026-05-26 07:17 UTCEPSS rescore
  57. 2026-05-26 05:52 UTCEG score recompute

Frequently asked(5)

What is CVE-2021-44548?
CVE-2021-44548 is a critical vulnerability published on December 23, 2021. An Improper Input Validation vulnerability in DataImportHandler of Apache Solr allows an attacker to provide a Windows UNC path resulting in an SMB network call being made from the Solr host to another host on the network. If the attacker has wider access to the network, this may lead to SMB…
When was CVE-2021-44548 disclosed?
CVE-2021-44548 was first published in the National Vulnerability Database on December 23, 2021, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-44548 actively exploited?
CVE-2021-44548 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 91.3% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2021-44548?
CVE-2021-44548 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2021-44548?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-44548, 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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