Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f1c8d8745333556…

MALICIOUS

PDF

68.1 KB Created: 2020-12-06 18:45:47 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 92c8775e1549cd1df271fd26fa7d575d SHA-1: 878150c1c4f158aeeb1eb6fe3026f4776a319d47 SHA-256: 8f1c8d87453335561ff67b8080cf1f4f38cc6e54e31a2f3f076fdfdc2fbf4c93
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of external links, many of which are to other PDFs, suggesting a link farm or SEO spamming operation. One of the embedded URIs, 'https://trafffi.ru/strik?utm_term=basd+google+apps', is likely a malicious redirect. The ML classifier also flagged this PDF as malicious with high confidence.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 4

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://trafffi.ru/strik?utm_term=basd+google+apps PDF link annotation
    • https://tedumuwoke.weebly.com/uploads/1/3/1/3/131397970/5095107.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368475/normal_5fa2c54198717.pdfIn PDF document text
    • https://jenafowumavadas.weebly.com/uploads/1/3/1/4/131437472/zokisizovisom.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4378623/normal_5f90d2cacd4be.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/c19adf68-ba10-4796-894d-d4ad7fde8594/muzavukufudemixubokodu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/55a2d8dc-33e2-4335-a34a-7be07270e42a/morse_4300_sewing_machine_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a52b5e8b-9b50-4ff9-97ac-c37ed311af3e/pumug.pdfIn PDF document text
    • https://static1.squarespace.com/static/5fbfd2c30b6b03258f2f7c3b/t/5fc13f26eaf37e3b64c9a831/1606500135517/disaridojajo.pdfIn PDF document text
    • https://s3.amazonaws.com/xeroguru/tefal_air_fryer_recipes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a58b03a4-c0aa-4eb0-ab57-84c84b98d2e0/lowopujomegovalate.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cf62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF62 5080 bytes
SHA-256: 36808b83d9fea6cd81a4edd07dbe8b3d77d678b1845822da2b52287a3af3214c
font_01_sfnt_off0000e0c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0C4 10388 bytes
SHA-256: 9eb7f7f3457bf959e9bb432ef92d59132f666d3c2ff84357379b6b34a20eaa64