Malicious PDF — malware analysis report

Static analysis result for SHA-256 b435375130d1963a…

MALICIOUS

PDF

74.2 KB Created: 2021-05-23 08:24:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 8cfe8452d33c9f8f7c339e6fdb520971 SHA-1: 3838039ea00b27a1cbb51d3d809c937dd6c2a958 SHA-256: b435375130d1963a77b966f461bbc681d8975e45680793e1dd153a392e1672b2
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 phishing or trojan threat. It contains a large number of external links, many pointing to disposable domains, suggesting it functions as a link farm. The presence of embedded URLs and the PDF_SEO_LINK_FARM heuristic strongly indicate an attempt to redirect users to potentially harmful content or facilitate SEO manipulation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 6

  • 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
  • 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://botokaw.ru/strik?utm_term=turkey+meatloaf+calories
    • https://sopunarexij.weebly.com/uploads/1/3/1/8/131857112/zuwikinuseror-zofivijixojele-rexodetusufefo.pdf
    • https://numokafi.weebly.com/uploads/1/3/2/6/132695525/jaxasufugumurakotow.pdf
    • https://tagenomamoz.weebly.com/uploads/1/3/4/4/134476715/9740743.pdf
    • https://tisalupiruj.weebly.com/uploads/1/3/4/0/134018152/8778452.pdf
    • https://lerozezowigex.weebly.com/uploads/1/3/0/7/130776164/1699254.pdf
    • https://bimuxafidiw.weebly.com/uploads/1/3/4/7/134701061/837526.pdf
    • https://static.s123-cdn-static.com/uploads/4369149/normal_5ff82c7729e14.pdf
    • https://rujedupexiveviz.weebly.com/uploads/1/3/4/8/134874221/2c305175904e.pdf
    • https://static.s123-cdn-static.com/uploads/4453754/normal_5fee859015f74.pdf
    • https://womegirig.weebly.com/uploads/1/3/4/5/134506381/nujuvowagalemifikaj.pdf
    • https://fatomomome.weebly.com/uploads/1/3/1/6/131606630/vunosunodoxegigopix.pdf
    • https://static.s123-cdn-static.com/uploads/4489716/normal_5fef103f8c4f3.pdf
    • https://static.s123-cdn-static.com/uploads/4483082/normal_5fff7ea1ba371.pdf
    • https://fumewalifo.weebly.com/uploads/1/3/4/8/134884483/benuxug.pdf
    • https://buzufurabobozu.weebly.com/uploads/1/3/5/3/135304208/8223893.pdf
    • https://cdn-cms.f-static.net/uploads/4469365/normal_601fdffc70d38.pdf
    • https://tokuniti.weebly.com/uploads/1/3/4/3/134331772/deron_diridupo_gakamivajovoja_vujanefajirenil.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/begijufadi/autocad_architecture_2018_free_trial.pdf
    • https://uploads.strikinglycdn.com/files/cf7a761a-8c5a-4ac6-aa08-b10c846b20cf/46848591488.pdf
    • https://uploads.strikinglycdn.com/files/57c5ac5e-190a-460f-897e-7378773feabd/how_to_program_your_comcast_remote_to_your_samsung_tv.pdf
    • https://uploads.strikinglycdn.com/files/c0400819-a875-470d-83c9-af1d78e49be7/sap_purchasing_outline_agreement_table.pdf
    • https://uploads.strikinglycdn.com/files/71cfe1ef-a1df-4a8f-a31b-0c7e631c4d3c/zimefuf.pdf
    • https://s3.amazonaws.com/rokuwapesu/flute_flight_of_the_bumblebee_sheet_music.pdf
    • https://s3.amazonaws.com/fipijife/barnett_game_crusher_3._0_manual.pdf
    • https://uploads.strikinglycdn.com/files/9c7c87b9-3049-462f-9a6f-08799a394f41/kiduzidorirowa.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_off0000e49b.bin
5f729bb568e2014cd2b716266f16dbbee7a2c7a479c1aca74660dbc9fe9e6896
pdf-font-stream PDF embedded font (sfnt) at offset 0xE49B 5140 bytes
font_01_sfnt_off0000f611.bin
6cc5d71139b889f4031704f2fb14030bceeabc46a8a6976ad0c7510afd55e2fc
pdf-font-stream PDF embedded font (sfnt) at offset 0xF611 10884 bytes