CVE-2021-47001

MEDIUMNVD 4.74.7
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to NVD's CVSS score.

Score 4.7 from GitHub Security Advisory published 2024-02-28. NVD baseline CVSS 4.7; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, NVD CVSS v3
Trending — 3 sources updated this week
4.7EG
EchelonGraph verdictMonitorRemediate within your standard update timelines (the SSVC decision on this page).
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.7%CVSS: 4.7Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

In the Linux kernel, the following vulnerability has been resolved:

xprtrdma: Fix cwnd update ordering

After a reconnect, the reply handler is opening the cwnd (and thus enabling more RPC Calls to be sent) /before/ rpcrdma_post_recvs() can post enough Receive WRs to receive their replies. This causes an RNR and the new connection is lost immediately.

The race is most clearly exposed when KASAN and disconnect injection are enabled. This slows down rpcrdma_rep_create() enough to allow the send side to post a bunch of RPC Calls before the Receive completion handler can invoke ib_post_recv().

CVSS v3
4.7
EG Score
4.7MEDIUMmedium confidence
EG Risk
21
EG Risk 21/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity47% × 45%
Impact severity (EG Severity): CVSS 4.7 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.8% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at every mission impact level.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (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.
EPSS PROB
0.7%
EPSS %ILE
54th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (4.7): severity, escalated by confirmed exploitation. This CVE's 4.7 is its impact severity (EG Severity), not escalated.

EG Severity
4.7 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.7% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-17). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.

A fix is available. Apply it within your standard update timelines.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (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

BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

February 28, 2024

Last Modified

August 5, 2026

Patch Availability(6)

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
linux—
  • every version up to 5.10.38-1: fixed in 5.10.38-1
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
linux—
  • every version up to 5.10.38-1: fixed in 5.10.38-1
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
linux—
  • every version up to 5.10.38-1: fixed in 5.10.38-1
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
linux—
  • every version up to 5.10.38-1: fixed in 5.10.38-1
—

All Vendor Advisories

(6)

Data Freshness Timeline

(refreshed 9× in last 7d / 34× 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 97 of 201 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. 3 repeat rows among the latest 100 are merged into the row they repeat. The 104 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-23 16:28 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  2. 2026-10-22 16:29 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  3. 2026-10-21 16:28 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  4. 2026-10-20 16:28 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  5. 2026-10-19 16:28 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  6. 2026-10-19 13:25 UTCOSV refresh
  7. 2026-10-18 16:28 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  8. 2026-10-18 08:50 UTCEG score recompute
  9. 2026-10-17 16:29 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  10. 2026-10-16 16:34 UTCEPSS rescoreEPSS 0.7% · 54th percentile
  11. 2026-10-15 16:28 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  12. 2026-10-14 16:29 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  13. 2026-10-13 16:28 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  14. 2026-10-12 19:05 UTCEG score recompute
  15. 2026-10-12 16:30 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  16. 2026-10-11 23:31 UTCEG score recompute
  17. 2026-10-11 13:44 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  18. 2026-10-10 19:56 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  19. 2026-10-09 20:04 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  20. 2026-10-08 16:40 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  21. 2026-10-07 23:45 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  22. 2026-10-06 15:14 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  23. 2026-10-05 17:40 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  24. 2026-10-04 23:19 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  25. 2026-10-03 14:22 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
Show 72 more
  1. 2026-10-02 16:23 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  2. 2026-09-30 15:45 UTCEG score recompute
  3. 2026-09-30 15:00 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  4. 2026-09-29 15:15 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  5. 2026-09-28 13:47 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  6. 2026-09-26 20:33 UTCOSV refresh
  7. 2026-09-26 15:54 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  8. 2026-09-26 00:21 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  9. 2026-09-24 14:00 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  10. 2026-09-23 13:45 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  11. 2026-09-22 14:44 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  12. 2026-09-21 20:28 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  13. 2026-09-20 20:13 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  14. 2026-09-19 15:38 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  15. 2026-09-18 19:24 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  16. 2026-09-17 19:23 UTCEPSS rescoreEPSS 0.7% · 53rd percentile
  17. 2026-09-16 14:05 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  18. 2026-09-15 03:06 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  19. 2026-09-12 14:57 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  20. 2026-09-11 14:49 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  21. 2026-09-11 09:33 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  22. 2026-09-08 21:57 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  23. 2026-09-07 15:58 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  24. 2026-09-07 05:48 UTCOSV refresh
  25. 2026-09-06 13:45 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  26. 2026-09-05 15:25 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  27. 2026-09-04 13:57 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  28. 2026-09-04 05:03 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  29. 2026-09-02 14:09 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  30. 2026-09-01 13:51 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  31. 2026-08-30 19:14 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  32. 2026-08-30 01:19 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  33. 2026-08-28 21:38 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  34. 2026-08-27 14:22 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  35. 2026-08-26 14:43 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  36. 2026-08-25 13:46 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  37. 2026-08-24 14:13 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  38. 2026-08-21 23:46 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  39. 2026-08-20 22:52 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  40. 2026-08-20 15:31 UTCOSV refresh
  41. 2026-08-19 17:01 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  42. 2026-08-18 13:45 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  43. 2026-08-17 13:44 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  44. 2026-08-16 14:53 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  45. 2026-08-16 02:11 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  46. 2026-08-15 01:27 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  47. 2026-08-13 21:57 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  48. 2026-08-12 13:48 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  49. 2026-08-11 13:38 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  50. 2026-08-09 13:44 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  51. 2026-08-08 16:34 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  52. 2026-08-07 16:24 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  53. 2026-08-06 13:44 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  54. 2026-08-05 19:15 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  55. 2026-08-05 09:44 UTCEG score recompute
  56. 2026-08-05 09:44 UTCGHSA enrichmentGHSA-h3qj-j9m5-8ffr · GitHub CVSS 4.7
  57. 2026-08-04 15:06 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  58. 2026-08-04 12:21 UTCEG score recompute
  59. 2026-08-04 12:21 UTCVendor advisory
  60. 2026-08-04 12:21 UTCGHSA enrichmentGHSA-h3qj-j9m5-8ffr · GitHub CVSS 4.7
  61. 2026-08-04 10:34 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  62. 2026-08-04 09:54 UTCEG score recompute
  63. 2026-08-04 09:54 UTCVendor advisory
  64. 2026-08-04 09:54 UTCGHSA enrichmentGHSA-h3qj-j9m5-8ffr · GitHub CVSS 4.7
  65. 2026-08-02 02:24 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  66. 2026-08-01 11:36 UTCOSV refresh
  67. 2026-08-01 04:13 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  68. 2026-07-30 16:25 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  69. 2026-07-30 01:28 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  70. 2026-07-28 15:33 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  71. 2026-07-26 14:52 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  72. 2026-07-25 14:15 UTCEPSS rescoreEPSS 0.3% · 20th percentile

Frequently asked(5)

What is CVE-2021-47001?
CVE-2021-47001 is a medium-severity vulnerability; its CVE record was published on February 28, 2024. In the Linux kernel, the following vulnerability has been resolved: xprtrdma: Fix cwnd update ordering After a reconnect, the reply handler is opening the cwnd (and thus enabling more RPC Calls to be sent) /before/ rpcrdmapostrecvs() can post enough Receive WRs to receive their replies. This causes…
When was the CVE record for CVE-2021-47001 published?
The CVE record for CVE-2021-47001 was published on February 28, 2024. 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 August 5, 2026; the record at its source may have been updated since.
Is CVE-2021-47001 actively exploited?
CVE-2021-47001 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.7% probability of exploitation in the next 30 days (54th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2021-47001?
CVE-2021-47001 has a CVSS v3 base score of 4.7 (NVD).
How do I remediate CVE-2021-47001?
A fix for CVE-2021-47001 is available: update to the fixed version the vendor names in its advisory.

Dependency Blast Radius

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