Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc1064b796c503da…

MALICIOUS

PDF

83.2 KB Created: 2021-03-28 10:06:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: de1cab14c5309d196bc75e1fb01bcbf5 SHA-1: 506203e8056ad187841df3cbcdf4e38d678752c3 SHA-256: fc1064b796c503da66ad1de6de143a9c460fb4cffa4cedcebfd9db3b4e9f315e
156 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 point to other PDFs, suggesting a link farm or redirection mechanism for malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, specifically phishing. While no scripts were explicitly extracted, the PDF structure and numerous external URIs are indicative of a phishing lure designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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/123?utm_term=idiot%2527+s+guide+to+baseball+rules
    • https://static.s123-cdn-static.com/uploads/4478378/normal_5fe33146708f5.pdf
    • https://cdn-cms.f-static.net/uploads/4481821/normal_603275ca01c79.pdf
    • https://cdn-cms.f-static.net/uploads/4474211/normal_601edc0737e78.pdf
    • https://mazefitarunakur.weebly.com/uploads/1/3/1/4/131453858/voful.pdf
    • https://cdn-cms.f-static.net/uploads/4481286/normal_601d8f82d0769.pdf
    • https://cdn-cms.f-static.net/uploads/4527164/normal_603a7fc032806.pdf
    • https://cdn-cms.f-static.net/uploads/4413019/normal_5fd6d902ea08c.pdf
    • https://sejirefado.weebly.com/uploads/1/3/4/6/134682993/fowadad.pdf
    • https://nigikejogu.weebly.com/uploads/1/3/4/9/134902550/dejubutox.pdf
    • https://cdn-cms.f-static.net/uploads/4419826/normal_605c61c04b0d1.pdf
    • https://static.s123-cdn-static.com/uploads/4452148/normal_5fe010bce98df.pdf
    • https://kakifimetuwojo.weebly.com/uploads/1/3/4/3/134317364/5b7a1f.pdf
    • https://vimedijo.weebly.com/uploads/1/3/1/6/131606629/zujuvabe.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://44f39d5c-a655-4437-91b6-62b11e148e71.filesusr.com/ugd/eb4c03_2e3c079045094bfa98e09f71abfd6e55.pdf?index=true
    • https://f61a8d15-835b-4c36-a3db-e4ead73ab13f.filesusr.com/ugd/e9f5f3_43dd1d81894f4375a8050aa105d0cb73.pdf?index=true
    • https://uploads.strikinglycdn.com/files/b714f2a3-a67a-4338-b164-9cd525cd9eab/marine_corps_scout_sniper_school_quantico_virginia.pdf
    • https://uploads.strikinglycdn.com/files/6c9cef29-7ffb-44f4-b6b0-e13abba30089/what_is_casey_at_the_bat_about.pdf
    • https://ed7c5604-ec0f-4ae6-9d22-6d534b57d154.filesusr.com/ugd/1d5a3f_d557fe473dff403ea5f3693e7cf685ae.pdf?index=true
    • https://uploads.strikinglycdn.com/files/23acedcb-5d50-4cb9-8fd7-f4b78fa47f01/gawozepanosa.pdf
    • https://8546b567-499d-44cb-812b-f4cb210fa0cc.filesusr.com/ugd/1f0b74_70c4e83cced44ef8ab653af4b888e40b.pdf?index=true
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fcdd.bin
8a1741f2af5973fb35a9e43f598d71bcc92ca1e6ac045707274158f5bcf8e797
pdf-font-stream PDF embedded font (sfnt) at offset 0xFCDD 4880 bytes
font_01_sfnt_off00010d86.bin
27673aead4261d54d1f304d8a714f42aa7b0917cd0a3c25a683dab4da0e12607
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D86 10568 bytes
font_02_sfnt_off000131a2.bin
d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378
pdf-font-stream PDF embedded font (sfnt) at offset 0x131A2 4324 bytes