Malicious PDF — malware analysis report

Static analysis result for SHA-256 a90db46cb5474939…

MALICIOUS

PDF

59.8 KB Created: 2021-06-04 14:52:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 3b0f1cff50bcfeb98cb9c21fc54dacc2 SHA-1: 3329fa82c99b9158b5978a5e458f57c50651dce7 SHA-256: a90db46cb5474939c0415bf0a00e9591225fddc135ff77540007ec9307403bfe
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains a large number of external links, many of which point to disposable hosting services, indicating a link farm designed to redirect users. The primary URL, 'https://ketchas.ru/pbw?utm_term=how+to+fix+a+broken+underground+dog+fence', is presented as a guide but likely serves as a lure to a phishing or malware distribution site. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9571

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-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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
  • 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://ketchas.ru/pbw?utm_term=how+to+fix+a+broken+underground+dog+fence
    • https://static.s123-cdn-static.com/uploads/4428083/normal_5fd092ac0d985.pdf
    • https://rowimunikak.weebly.com/uploads/1/3/5/3/135346477/dce7a956d838bd8.pdf
    • https://gogafijunovox.weebly.com/uploads/1/3/4/3/134322332/e3e6656978cc36.pdf
    • https://zisafidavilux.weebly.com/uploads/1/3/2/8/132814196/5574536.pdf
    • https://static.s123-cdn-static.com/uploads/4414680/normal_5fc85690f1fcf.pdf
    • https://zugatesek.weebly.com/uploads/1/3/6/0/136082504/pavipemekixafi-gaxotixavolanu.pdf
    • https://varusotefus.weebly.com/uploads/1/3/1/3/131398431/6899548.pdf
    • https://dineretisa.weebly.com/uploads/1/3/4/7/134709889/795ad6.pdf
    • https://xibemorebag.weebly.com/uploads/1/3/4/3/134355918/sekibevarefo_pizitititupinev_vizono.pdf
    • https://regifedemez.weebly.com/uploads/1/3/1/4/131406591/lotegimufaxefupet.pdf
    • https://rivoliga.weebly.com/uploads/1/3/5/3/135311175/1294081.pdf
    • https://pixabetamomu.weebly.com/uploads/1/3/1/0/131070001/jilunidibeb.pdf
    • http://ririgifavem.pbworks.com/w/file/fetch/144594699/what_are_the_roles_and_responsibilities_of_a_government_accountant.pdf
    • https://uploads.strikinglycdn.com/files/a64ec641-0bdd-49fd-8f68-542d9c8e6e54/oily_hair_shampoo_solutions.pdf
    • http://risuxujuvu.pbworks.com/f/gasorijagag.pdf
    • http://mujefapufefi.pbworks.com/f/50768914719.pdf
    • http://zajozote.pbworks.com/w/file/fetch/144447504/75177413408.pdf
    • https://uploads.strikinglycdn.com/files/e4fcec28-b04f-4eb9-87e5-ec7d2485c721/insidious_3_full_movie_in_hindi_download_filmywap.pdf
    • http://fubajulak.pbworks.com/f/dotodijozovopuviveze.pdf

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d808.bin
d8b907802410e675ceca2784509e58a9dae2947c1b2ad43e3e0c02687eabed47
pdf-font-stream PDF embedded font (sfnt) at offset 0xD808 2952 bytes