CVE-2026-20248

MEDIUMPre-NVD 6.86.8
EchelonGraph scoreMEDIUM confidence

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

Score 6.8 from GitHub Security Advisory (severity: MODERATE) published 2026-09-16. The CNA's CVSS baseline 6.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: the CNA's CVSS, EPSS, GitHub Security Advisory

Also known asEUVD-2026-81143 (ENISA EUVD) · GHSA-qxw6-2w65-g7rg (GitHub Security Advisories)Source: ENISA EUVD

6.8EG
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: 0.5%CVSS: 6.8Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

A vulnerability in the DNS over TCP implementation of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the TCP DNS response handler to unexpectedly restart, causing the device to reload. This vulnerability is due to a logic error when parsing a DNS query and tracking the size of the incoming buffers. An attacker could exploit this vulnerability by formatting a crafted reply to a DNS query sent from the targeted device. A successful exploit could allow the attacker to cause the device to reload, causing a denial of service (DoS) condition. Note: The attacker must be able to respond to DNS queries from the device, either by controlling the DNS service or through a machine-in-the-middle attack.

CVSS v3
6.8
EG Score
6.8MEDIUMmedium confidence
EG Risk
31
EG Risk 31/100

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)
Severity68% × 45%
Impact severity (EG Severity): CVSS 6.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.5% × 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
0.5%
EPSS %ILE
39th
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 (6.8): severity, escalated by confirmed exploitation. This CVE's 6.8 is its impact severity (EG Severity), not escalated.

EG Severity
6.8 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.5% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-07). 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, and whom BOD 26-04 binds: 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.

The score's inputs: 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

September 16, 2026

Last Modified

September 18, 2026

Advisory Details (1)

Auto-updated Sep 16, 2026
Patch available.
Web page

Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software TCP DNS Denial of Service Vulnerability

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-tcpdns-dos-p6dUnjr5

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 8× in last 7d / 32× 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 its CVE.org record (CNA or CISA ADP). 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). "EchelonGraph re-scored" is our own recompute of this CVE's score, not an update from a source, and is not counted in the refreshes above. Most recent first.

Showing the most recent 100 of 114 rows 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. None are among the latest 100 rows. The 14 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-13 16:51 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  2. 2026-11-12 16:33 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  3. 2026-11-11 16:39 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  4. 2026-11-10 16:42 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  5. 2026-11-09 16:34 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  6. 2026-11-08 16:38 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  7. 2026-11-07 19:42 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub severity MODERATE · GitHub CVSS 6.8
  8. 2026-11-07 19:42 UTCEchelonGraph re-scored
  9. 2026-11-07 16:38 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  10. 2026-11-06 16:37 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  11. 2026-11-05 16:37 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  12. 2026-11-04 16:35 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  13. 2026-11-03 16:47 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  14. 2026-11-02 16:44 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  15. 2026-11-01 16:34 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  16. 2026-10-31 16:32 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  17. 2026-10-30 16:34 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  18. 2026-10-29 16:32 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  19. 2026-10-28 16:31 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  20. 2026-10-27 16:31 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  21. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  22. 2026-10-25 16:32 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  23. 2026-10-25 14:44 UTCEchelonGraph re-scored
  24. 2026-10-24 16:32 UTCEPSS rescoreEPSS 0.3% · 26th percentile
  25. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.3% · 26th percentile
Show 75 more
  1. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.3% · 26th percentile
  2. 2026-10-21 16:32 UTCEPSS rescoreEPSS 0.3% · 26th percentile
  3. 2026-10-20 16:32 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  4. 2026-10-19 16:31 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  5. 2026-10-18 16:31 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  6. 2026-10-18 03:57 UTCEchelonGraph re-scored
  7. 2026-10-17 16:33 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  8. 2026-10-16 21:57 UTCEchelonGraph re-scored
  9. 2026-10-16 21:57 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  10. 2026-10-16 16:41 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  11. 2026-10-15 16:31 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  12. 2026-10-14 16:32 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  13. 2026-10-13 16:33 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  14. 2026-10-12 16:33 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  15. 2026-10-12 16:24 UTCEchelonGraph re-scored
  16. 2026-10-11 20:05 UTCEchelonGraph re-scored
  17. 2026-10-11 17:18 UTCEchelonGraph re-scored
  18. 2026-10-11 14:51 UTCEchelonGraph re-scored
  19. 2026-10-11 13:48 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  20. 2026-10-11 04:00 UTCEchelonGraph re-scored
  21. 2026-10-11 04:00 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  22. 2026-10-10 19:59 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  23. 2026-10-10 03:40 UTCEchelonGraph re-scored
  24. 2026-10-10 03:40 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  25. 2026-10-09 20:06 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  26. 2026-10-09 03:23 UTCEchelonGraph re-scored
  27. 2026-10-09 03:22 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  28. 2026-10-08 17:11 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  29. 2026-10-08 03:05 UTCEchelonGraph re-scored
  30. 2026-10-08 03:05 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  31. 2026-10-07 23:47 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  32. 2026-10-07 02:48 UTCEchelonGraph re-scored
  33. 2026-10-07 02:48 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  34. 2026-10-06 15:17 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  35. 2026-10-06 02:31 UTCEchelonGraph re-scored
  36. 2026-10-06 02:31 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  37. 2026-10-05 17:42 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  38. 2026-10-05 02:14 UTCEchelonGraph re-scored
  39. 2026-10-05 02:14 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  40. 2026-10-04 23:21 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  41. 2026-10-04 01:57 UTCEchelonGraph re-scored
  42. 2026-10-04 01:57 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  43. 2026-10-03 01:40 UTCEchelonGraph re-scored
  44. 2026-10-03 01:40 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  45. 2026-10-02 01:23 UTCEchelonGraph re-scored
  46. 2026-10-02 01:23 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  47. 2026-10-01 19:49 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  48. 2026-10-01 01:06 UTCEchelonGraph re-scored
  49. 2026-10-01 01:06 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  50. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  51. 2026-09-30 00:50 UTCEchelonGraph re-scored
  52. 2026-09-30 00:49 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  53. 2026-09-29 15:21 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  54. 2026-09-28 23:25 UTCEchelonGraph re-scored
  55. 2026-09-28 23:25 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  56. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  57. 2026-09-27 23:08 UTCEchelonGraph re-scored
  58. 2026-09-27 23:08 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  59. 2026-09-27 13:47 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  60. 2026-09-26 22:50 UTCEchelonGraph re-scored
  61. 2026-09-26 22:50 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  62. 2026-09-26 15:58 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  63. 2026-09-26 00:26 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  64. 2026-09-25 22:34 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  65. 2026-09-24 21:31 UTCEchelonGraph re-scored
  66. 2026-09-24 21:31 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  67. 2026-09-24 14:03 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  68. 2026-09-23 20:45 UTCEchelonGraph re-scored
  69. 2026-09-23 20:45 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  70. 2026-09-22 20:28 UTCEchelonGraph re-scored
  71. 2026-09-22 20:28 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  72. 2026-09-21 20:11 UTCEchelonGraph re-scored
  73. 2026-09-21 20:11 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8
  74. 2026-09-20 20:15 UTCEPSS rescoreEPSS 0.3% · 27th percentile
  75. 2026-09-20 19:54 UTCGHSA enrichmentGHSA-qxw6-2w65-g7rg · GitHub CVSS 6.8

Frequently asked(5)

What is CVE-2026-20248?
CVE-2026-20248 is a medium-severity vulnerability; its CVE record was published on September 16, 2026. A vulnerability in the DNS over TCP implementation of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the TCP DNS response handler to unexpectedly restart, causing…
When was the CVE record for CVE-2026-20248 published?
The CVE record for CVE-2026-20248 was published on September 16, 2026. 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 September 18, 2026; the record at its source may have been updated since.
Is CVE-2026-20248 actively exploited?
CVE-2026-20248 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.5% probability of exploitation in the next 30 days (39th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-20248?
CVE-2026-20248 has a CVSS base score of 6.8 (the CNA's own assessment, by cisco; NVD's own analysis pending).
How do I remediate CVE-2026-20248?
A fix for CVE-2026-20248 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-20248 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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