Malicious PDF — malware analysis report

Static analysis result for SHA-256 5ffe990731f28f8b…

MALICIOUS

PDF

72.6 KB Created: 2021-06-09 20:19:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: c2022ad900b8ef0477cd78b5fd8b9aab SHA-1: cf5b6eac978d648014be440147486ef302e0ea62 SHA-256: 5ffe990731f28f8b5103ac9f60b8db7a6d7d0d1fe278628affed1154ac55a68d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a large number of external links, many hosted on disposable domains, indicating a link farm or SEO manipulation tactic. The ML classifier strongly flagged this PDF as malicious. The embedded URLs suggest the document is intended to redirect users to potentially harmful content or further stages of an attack.

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.
  • 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://queure.ru/pbw?utm_term=no+download+battle+royale+games PDF link annotation
    • https://gemonozuwusub.weebly.com/uploads/1/3/4/1/134131657/sejilojete.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4416322/normal_5fe29efe3e1a7.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4482230/normal_60b0ea933b962.pdfIn PDF document text
    • https://latewumopinigan.weebly.com/uploads/1/3/4/3/134313498/wuziguzuzu-rakojazedofe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4475197/normal_603634b9b08d7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4390664/normal_606035bd91829.pdfIn PDF document text
    • https://numufirunake.weebly.com/uploads/1/3/5/3/135301026/sareponuge.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4413363/normal_5fdf6601cafb8.pdfIn PDF document text
    • https://ponuxarazuzega.weebly.com/uploads/1/3/5/3/135328107/moluz-zufefovij-puremetekogek.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4496360/normal_60250254eea3f.pdfIn PDF document text
    • https://jikodidujur.weebly.com/uploads/1/3/5/3/135319234/sezenarivanofunopa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426085/normal_6047a29ad4ac2.pdfIn PDF document text
    • https://xidasosi.weebly.com/uploads/1/3/4/7/134722002/pomum.pdfIn PDF document text
    • https://tatudibew.weebly.com/uploads/1/3/0/8/130813899/707ade055.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/35b55eb8-4dc0-40a2-bafa-c8cdc65899f2/introduction_to_data_science.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/308f6f99-1660-4baa-a029-a6d1e2345844/borerurikatowo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/863b78a7-547f-4a7b-93e4-52bbdf2b88e4/21264194972.pdfIn PDF document text
    • http://gosavepifij.pbworks.com/w/file/fetch/144926289/2386221403.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/74fdb3c6-8699-4ca7-9ba6-d195bd85e08c/what_are_the_main_beliefs_of_buddhism_confucianism_and_taoism.pdfIn PDF document text
    • http://tejudafo.pbworks.com/w/file/fetch/144818469/56663094058.pdfIn PDF document text
    • http://zakikumese.pbworks.com/f/myles_munroe_books_on_kingdom.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c4350761-f1d2-4cb1-8172-50e989792492/how_to_take_apart_a_keurig_duo.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000de56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE56 5448 bytes
SHA-256: 95ac2dd84b67efe69ef937ce6ed3944a694c3db5ddae136fb8bbac3a1d18fbce
font_01_sfnt_off0000f0e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0E2 10892 bytes
SHA-256: 3495d0b18ebdb721c4595aba2e0b3801c129553d52d2f98ab34ff1ad0295b5b9