CVE-2026-18738

MEDIUMPre-NVD 4.74.7
EchelonGraph scoreMEDIUM confidence

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

Score 4.7 from GitHub Security Advisory published 2026-08-03. A secondary CVSS source baseline 4.7; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, a secondary CVSS source
Trending — 3 sources updated this week

Also known asEUVD-2026-52439 (ENISA EUVD) · GHSA-ghrv-q878-w45x (GitHub Security Advisories)Source: ENISA EUVD

4.7EG
EchelonGraph verdictMonitorNo fix is confirmed yet: check the vendor's advisory for a fixed release; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.5%CVSS: 4.7Exploit: None knownExposed services: Not assessed

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

The CVE record's description, written by its CNA (VulnCheck), states the affected versions: "Shlink versions 5.0.0 through 5.1.5 contain a CSV formula injection vulnerability that allows unauthenticated remote attackers to plant spreadsheet formulas into exported visit data by supplying malicious values in User…" No release containing a fix is confirmed on record.

Shlink versions 5.0.0 through 5.1.5 contain a CSV formula injection vulnerability that allows unauthenticated remote attackers to plant spreadsheet formulas into exported visit data by supplying malicious values in User-Agent, Referer, or request path headers beginning with formula-triggering characters such as =, +, -, or @. Attackers can craft a single unauthenticated request against any short URL to embed DDE or WEBSERVICE formula payloads into CSV cells, which are then executed on an administrator's client machine when the exported CSV file is opened in a spreadsheet application that evaluates formulas.

CVSS v3
4.7
EG Score
4.7MEDIUMmedium confidence
EG Risk
36
EG Risk 36/100

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.
Exploitation0.5% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).
Exploitation none (CISA Vulnrichment) · Automatable yes (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: No fix is confirmed yet. Check the vendor's advisory for a fixed release; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high.
EPSS PROB
0.5%
EPSS %ILE
42nd
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
0.5% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-28). 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 low or medium mission impact; Attend at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; 60 days if it is not.No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says.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 low or medium mission impact; Attend at high (mission-essential systems).

No fix is confirmed yet. Check the vendor's advisory for a fixed release; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high.

Exploitation none (CISA Vulnrichment) · Automatable yes (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)14 days if the affected system is publicly exposed; 60 days if it is not.

No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable yes (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

August 3, 2026

Last Modified

October 23, 2026

Advisory Details (3)

Auto-updated Aug 3, 2026
No fix on record yet.
Web page

Shlink CSV Formula Injection via Visit Export CLI | Advisories | VulnCheck

https://www.vulncheck.com/advisories/shlink-csv-formula-injection-via-visit-export-cli
Web page

GitHub - theopaid/CSV-formula-injection-in-visit-exports-shlink-: Security Advisory: CSV formula injection in visit exports (shlink) · GitHub

https://github.com/theopaid/CSV-formula-injection-in-visit-exports-shlink-
Web page

GitHub - shlinkio/shlink: The definitive self-hosted URL shortener · GitHub

https://github.com/shlinkio/shlink

Vendor Advisories for CVE-2026-18738(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 9× in last 7d / 48× 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 100 of 190 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. None are among the latest 100 rows. The 90 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-02 16:44 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  2. 2026-11-01 16:34 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  3. 2026-10-31 16:32 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  4. 2026-10-30 16:33 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  5. 2026-10-29 16:32 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  6. 2026-10-29 16:00 UTCEG score recompute
  7. 2026-10-29 16:00 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  8. 2026-10-28 16:31 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  9. 2026-10-27 16:31 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  10. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  11. 2026-10-25 16:32 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  12. 2026-10-25 14:45 UTCEG score recompute
  13. 2026-10-24 16:32 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  14. 2026-10-23 21:33 UTCEG score recompute
  15. 2026-10-23 21:33 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  16. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  17. 2026-10-23 05:58 UTCEG score recompute
  18. 2026-10-23 05:58 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  19. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  20. 2026-10-21 16:32 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  21. 2026-10-20 16:32 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  22. 2026-10-19 16:31 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  23. 2026-10-18 16:31 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  24. 2026-10-18 03:58 UTCEG score recompute
  25. 2026-10-17 16:33 UTCEPSS rescoreEPSS 0.5% · 41st percentile
Show 75 more
  1. 2026-10-16 16:40 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  2. 2026-10-15 16:31 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  3. 2026-10-14 16:32 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  4. 2026-10-13 16:33 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  5. 2026-10-12 16:33 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  6. 2026-10-12 16:27 UTCEG score recompute
  7. 2026-10-11 20:07 UTCEG score recompute
  8. 2026-10-11 17:20 UTCEG score recompute
  9. 2026-10-11 14:52 UTCEG score recompute
  10. 2026-10-11 13:48 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  11. 2026-10-10 19:59 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  12. 2026-10-09 20:06 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  13. 2026-10-08 17:11 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  14. 2026-10-07 23:47 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  15. 2026-10-06 23:45 UTCEG score recompute
  16. 2026-10-06 23:45 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  17. 2026-10-06 15:17 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  18. 2026-10-05 19:46 UTCEG score recompute
  19. 2026-10-05 19:46 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  20. 2026-10-05 17:42 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  21. 2026-10-04 23:21 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  22. 2026-10-04 06:17 UTCEG score recompute
  23. 2026-10-04 06:17 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  24. 2026-10-02 10:17 UTCEG score recompute
  25. 2026-10-02 10:17 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  26. 2026-10-01 19:49 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  27. 2026-10-01 02:31 UTCEG score recompute
  28. 2026-10-01 02:31 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  29. 2026-09-30 15:02 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  30. 2026-09-29 15:20 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  31. 2026-09-29 06:32 UTCEG score recompute
  32. 2026-09-29 06:32 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  33. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  34. 2026-09-27 18:14 UTCEG score recompute
  35. 2026-09-27 18:14 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  36. 2026-09-27 13:47 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  37. 2026-09-26 15:58 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  38. 2026-09-24 08:20 UTCEG score recompute
  39. 2026-09-24 08:20 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  40. 2026-09-23 06:06 UTCEG score recompute
  41. 2026-09-23 06:06 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  42. 2026-09-22 03:52 UTCEG score recompute
  43. 2026-09-22 03:52 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  44. 2026-09-20 11:04 UTCEG score recompute
  45. 2026-09-20 11:04 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  46. 2026-09-19 08:00 UTCEG score recompute
  47. 2026-09-19 08:00 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  48. 2026-09-18 19:27 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  49. 2026-09-18 03:27 UTCEG score recompute
  50. 2026-09-18 03:27 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  51. 2026-09-17 01:13 UTCEG score recompute
  52. 2026-09-17 01:13 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  53. 2026-09-16 14:07 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  54. 2026-09-16 05:14 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  55. 2026-09-15 16:54 UTCEG score recompute
  56. 2026-09-15 16:54 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  57. 2026-09-14 07:55 UTCEG score recompute
  58. 2026-09-14 07:55 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  59. 2026-09-13 16:46 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  60. 2026-09-13 05:41 UTCEG score recompute
  61. 2026-09-13 05:41 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  62. 2026-09-12 15:00 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  63. 2026-09-12 03:27 UTCEG score recompute
  64. 2026-09-12 03:27 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  65. 2026-09-11 14:52 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  66. 2026-09-11 09:36 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  67. 2026-09-11 01:12 UTCEG score recompute
  68. 2026-09-11 01:12 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  69. 2026-09-10 09:34 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  70. 2026-09-09 21:04 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  71. 2026-09-09 06:42 UTCEG score recompute
  72. 2026-09-09 06:42 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7
  73. 2026-09-08 22:00 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  74. 2026-09-07 18:46 UTCEG score recompute
  75. 2026-09-07 18:46 UTCGHSA enrichmentGHSA-ghrv-q878-w45x · GitHub CVSS 4.7

Frequently asked(5)

What is CVE-2026-18738?
CVE-2026-18738 is a medium-severity vulnerability; its CVE record was published on August 3, 2026. Shlink versions 5.0.0 through 5.1.5 contain a CSV formula injection vulnerability that allows unauthenticated remote attackers to plant spreadsheet formulas into exported visit data by supplying malicious values in User-Agent, Referer, or request path headers beginning with formula-triggering…
When was CVE-2026-18738 made public?
CVE-2026-18738 was made public on August 3, 2026: that is the date its CVE record's CNA, VulnCheck, gives for when the vulnerability was made public. The CVE record itself was published on August 3, 2026. EchelonGraph's copy of the record carries a last-modified date of October 23, 2026; the record at its source may have been updated since.
Is CVE-2026-18738 actively exploited?
CVE-2026-18738 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.5% probability of exploitation in the next 30 days (42nd percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-18738?
CVE-2026-18738 has a CVSS base score of 4.7 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-18738?
No fix for CVE-2026-18738 is confirmed yet. Until one is published, restrict network exposure of the affected system or apply the vendor's mitigation — for example, keep it off the internet or limit it to trusted networks — and watch the vendor's advisory for the fix. The CVE record's description, written by its CNA (VulnCheck), states the affected versions: "Shlink versions 5.0.0 through 5.1.5 contain a CSV formula injection vulnerability that allows unauthenticated remote attackers to plant spreadsheet formulas into exported visit data by supplying malicious values in User…" No release containing a fix is confirmed on record. The vendor advisories EchelonGraph has for CVE-2026-18738 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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