Malicious PDF — malware analysis report

Static analysis result for SHA-256 cfd42b1322c99982…

MALICIOUS

PDF

89.3 KB Created: 2021-05-28 00:19:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: 3f3f8d1a872ff641012a2f15d9378f19 SHA-1: 10fbaa9c6e50f69a757937c87b76eee4b3a8e717 SHA-256: cfd42b1322c99982c6a74c6ea8ddfd49204f14534a4f7fbff68a91bb2e7bf857
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to numerous external URLs, including suspicious domains like pelibifir.ru and weebly.com subdomains. The presence of embedded URLs and the PDF_SEO_LINK_FARM heuristic suggest the document's primary purpose is to redirect users to potentially harmful content or phishing sites. No scripts were extracted, but the overall structure points to a phishing or content-luring attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://pelibifir.ru/strik?utm_term=how+to+lose+weight+fast+without+diet+pills+or+exercise PDF link annotation
    • https://xedatuvigino.weebly.com/uploads/1/3/4/5/134580066/wobego.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4418381/normal_601f73a092021.pdfIn PDF document text
    • https://gajaxaja.weebly.com/uploads/1/3/2/7/132712369/jasebuwo.pdfIn PDF document text
    • https://redunexodozik.weebly.com/uploads/1/3/0/8/130814050/82aa80.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4417643/normal_600608f2715af.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4462350/normal_601f2aa9f2b6c.pdfIn PDF document text
    • https://nusupubibirimu.weebly.com/uploads/1/3/1/8/131871553/9289118facb3d49.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4451229/normal_5fdd268385ab0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384652/normal_602057b5bd5cc.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4450728/normal_600080c5bb2ad.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408862/normal_600f933f01daa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415544/normal_602e9ba3ee217.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4371269/normal_60b008f666ab7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459937/normal_606e80a8916c1.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/828adc5d-cebe-4e82-b425-902cdd1af16f/dupabi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bf9ffe01-e4d2-4ef9-8aaa-6061c34b3edf/does_katniss_mom_die.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2a3b264e-9664-4996-9faa-af4d91f6137f/59444372737.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bb41b831-4e5f-41e1-b8fc-f533a34c5998/remekakuvorum.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/603855f2-0368-4ff8-ae4d-90d4d3cadbcf/tejukodoxiji.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000108dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108DD 5540 bytes
SHA-256: 8733043ff162d76988dd13275f9c4492ba882e137fbe18bd7ab1e9e2a096d55d
font_01_sfnt_off00011bc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BC5 11632 bytes
SHA-256: 0be327ce7ae0c3d3173b86d4e7306f0ec528260227a5e6b16abaddf2133577d4
font_02_sfnt_off000142c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x142C5 16060 bytes
SHA-256: 2173a1880e9f774f759393e7d0d28dda91d04d8a3eae6bea41b822770b343b90