Malicious PDF — malware analysis report

Static analysis result for SHA-256 81e1c77529b3b295…

MALICIOUS

PDF

74.0 KB Created: 2021-05-30 11:01:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c9c0fdf5a301d70a602774c91f27e412 SHA-1: f338b5e9d073c87e95e75d1c6f339cdf3665a386 SHA-256: 81e1c77529b3b2954435ae5feeeafd8296403bb8347149553a4c8af8f4e217bc
156 Risk Score

Malware Insights

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

The PDF file contains numerous external links, characteristic of a link farm designed to manipulate search engine results. The primary URL, 'https://resalured.ru/wb?keyword=whirlpool%20duet%20sport%20error%20code%20f01', suggests a lure related to appliance error codes, likely intended to direct users to a phishing or malware distribution site. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • 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://resalured.ru/wb?keyword=whirlpool%20duet%20sport%20error%20code%20f01
    • https://tavovoxiwazufaj.weebly.com/uploads/1/3/5/3/135325502/1720786.pdf
    • https://cdn-cms.f-static.net/uploads/4407810/normal_601cc8fb5e9ff.pdf
    • https://cdn-cms.f-static.net/uploads/4379237/normal_605f455d1b0ef.pdf
    • https://static.s123-cdn-static.com/uploads/4447631/normal_5ff65b1c9aab2.pdf
    • https://static.s123-cdn-static.com/uploads/4486190/normal_5ffea7b110dec.pdf
    • https://cdn-cms.f-static.net/uploads/4454671/normal_6023653b13776.pdf
    • https://cdn-cms.f-static.net/uploads/4446015/normal_6057b95ad2412.pdf
    • https://guvolobojifo.weebly.com/uploads/1/3/4/7/134733869/parutefisoberog_divevefefivixa_libedaroravene.pdf
    • https://static.s123-cdn-static.com/uploads/4482415/normal_5fcaf2f883f64.pdf
    • https://cdn-cms.f-static.net/uploads/4446490/normal_600e7fe1a10bc.pdf
    • https://cdn-cms.f-static.net/uploads/4480149/normal_603a1ef112e77.pdf
    • https://cdn-cms.f-static.net/uploads/4376382/normal_6064f01b7676a.pdf
    • https://cdn-cms.f-static.net/uploads/4367312/normal_6022cdaf30dc9.pdf
    • https://jugoneworo.weebly.com/uploads/1/3/4/3/134307205/237a3d66b9.pdf
    • https://tekoxinir.weebly.com/uploads/1/3/4/6/134606092/1010825.pdf
    • https://laxefozono.weebly.com/uploads/1/3/4/3/134361517/varobul-voxusupevizima.pdf
    • https://cdn-cms.f-static.net/uploads/4481540/normal_602da041eee4a.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/59b2a56b-4699-4008-bb3a-3164fdb4155f/mukiris.pdf
    • https://uploads.strikinglycdn.com/files/d56e7c7e-d235-4c29-89ef-8b3a53dda0fc/misojexufudixuw.pdf
    • https://uploads.strikinglycdn.com/files/d1c83666-a476-429d-9d0f-b7f65768e25c/how_to_activate_tableau_desktop.pdf
    • https://uploads.strikinglycdn.com/files/ebf3cb71-78b0-416c-9604-1c4a4f986790/how_much_is_the_lottery_2020.pdf
    • 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e440.bin
e3a77e2235e8ad08a54cff5b53c80748ac15564129a74415b0f63a6e28cfab8d
pdf-font-stream PDF embedded font (sfnt) at offset 0xE440 5240 bytes
font_01_sfnt_off0000f626.bin
838ebff205d4a33fa2fe2975bef2ec1aebd5b6512f396c8a4155387df0cbf251
pdf-font-stream PDF embedded font (sfnt) at offset 0xF626 10556 bytes