Malicious PDF — malware analysis report

Static analysis result for SHA-256 8bef3cd7726c0bc7…

MALICIOUS

PDF

84.1 KB Created: 2021-03-23 01:11:17 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: de72ffedcd48b957ac6a61e0cf19decd SHA-1: 770737589a53d01bf7042785641d4a20d95fb37a SHA-256: 8bef3cd7726c0bc7e7f074b1a46a4448380ab21c66b5af59aa1717196275ae63
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, indicating a link farm designed to direct users to potentially malicious websites. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and numerous external links are indicative of an attempt to redirect users, aligning with spearphishing tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://pelibifir.ru/wix?keyword=honeywell+rthl2310b1008+manual+pdf
    • http://fevofawemuwa.medianewsonline.com/nukadet.pdf
    • http://wutopezogegusi.getenjoyment.net/7032025828.pdf
    • http://rowaxamapitowej.getenjoyment.net/bozudufog.pdf
    • http://wusokamojifel.scienceontheweb.net/ielts_band_score_chart_academic.pdf
    • http://pagavopalubutu.scienceontheweb.net/15904002428.pdf
    • http://zetumitufam.mywebcommunity.org/baudelaire_paris_spleen.pdf
    • https://static.s123-cdn-static.com/uploads/4416935/normal_5fcf8339ad3d4.pdf
    • https://cdn-cms.f-static.net/uploads/4403414/normal_602af02992575.pdf
    • https://static.s123-cdn-static.com/uploads/4453718/normal_5ff70a0951eea.pdf
    • http://dejivuxa.mygamesonline.org/68106322898.pdf
    • http://dajexori.mypressonline.com/what_is_the_format_of_a_research_paper.pdf
    • https://static.s123-cdn-static.com/uploads/4475729/normal_5fe40a641b495.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://e0220c8c-c322-4c33-af83-7c5b0fe00b66.filesusr.com/ugd/a771bd_f92402e1c66a449aaa3ced0db31c1a4d.pdf?index=true
    • https://0c7ecde5-8d52-4b6d-bf00-bcb9beb5fd3c.filesusr.com/ugd/b6f5a5_0ff36a1a35364bee9c310b71bd19e2e8.pdf?index=true
    • https://d45380bd-a93d-4ef2-b2bd-4c7806d1f6db.filesusr.com/ugd/5d2cf3_0f40b81907c844d4b813f10e9e0c6dd5.pdf?index=true
    • http://dapizodipe.myartsonline.com/pathfinder_player_companion_ranged_tactics_toolbox.pdf
    • https://8d90b851-447f-4cfc-ac95-1e867b71b983.filesusr.com/ugd/b371d9_cebf198a8e55462d9e3a1a2928bd0183.pdf?index=true
    • https://04650017-3ca5-4b28-9d9b-11da2816551d.filesusr.com/ugd/aa03de_d529ec3f16284d08b1dda03b53849fcc.pdf?index=true
    • http://nununad.myartsonline.com/black_and_decker_drip_coffee_maker_with_grinder.pdf
    • https://ff06b2c9-6223-4357-b4d5-1bf3807c749f.filesusr.com/ugd/717131_fc0e44997f5d4ff4b26b25dcc8c14ac0.pdf?index=true
    • https://c33c3ce4-fa2f-4f19-9477-7a801b41b29e.filesusr.com/ugd/ebbcbd_a7a77e5f28c84ee7ae5d9ca8de8c7355.pdf?index=true
    • http://mobukug.myartsonline.com/capacity_building_books.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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off00012923.bin
b1bed9863b53a5a969ff7a449e361aa6c0526f1afa4c291ebf7e177919ff8922
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x12923 17352 bytes
font_00_sfnt_off0000ecfe.bin
f061cac717bf0de8efca740b2a8c69c0189ac34ebe662bd36685742c5d45577e
pdf-font-stream PDF embedded font (sfnt) at offset 0xECFE 6084 bytes
font_01_sfnt_off00010199.bin
6268c92435c18e87519ecb7067f108bb091c7bba6c6ea8e4c3182a475d561dfe
pdf-font-stream PDF embedded font (sfnt) at offset 0x10199 11716 bytes