Malicious PDF — malware analysis report

Static analysis result for SHA-256 ea93986732306d82…

MALICIOUS

PDF

83.0 KB Created: 2021-09-09 22:15:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 676da1b2ff17d3072f1b7e8bd9fc8108 SHA-1: aef2aab110e13c1fb19cbccdba00315e5d72b455 SHA-256: ea93986732306d82d42e0dd47bb1a2145ff7c670b6627f317856fbf471a5b6d8
156 Risk Score

Malware Insights

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

The sample is identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. It contains numerous links, many pointing to compromised CMS uploads and disposable hosting, suggesting a link farm designed to redirect users. The PDF's structure and embedded links indicate it's intended to lead users to malicious sites, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/18h14o9uaa6morcgd763a011t3/701770825.pdf
    • https://n-zvuk.ru/upload/file/58757876048.pdf
    • http://fotosvatba.net/userfiles/file/sewonujikusijenawikuguwek.pdf
    • http://music-summer-courses.eu/upload/files/letusalegazetaxag.pdf
    • https://phunhai.net/upload/files/85832129997.pdf
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/qvlvg5shns4fbn6tncit7g0ld6/sewadowafeludidudejakaw.pdf
    • https://expomediainc.com/upload/file/72241619090.pdf
    • https://cyklo-wellness-penzion-palice.cz/content/zeraxeropodafibajibizud.pdf
    • https://butterfly-propertymanagement.com/userfiles/file/56594591969.pdf
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/16137be295f352---poderitaregug.pdf
    • http://eternalcycle.com/FCKFiles/file/disuni.pdf
    • http://vladekoservis.ru/files/15420788919.pdf
    • http://rspon.pl/images/wyswig_images/file/31804248398.pdf
    • https://ev-owners.jp/userfiles/files/fovowunibapodulemuxi.pdf
    • http://goodfortune.hk/UpLoadFile/file///vufokunodilefurabasosin.pdf
    • https://majubesar.net/contents/files/gavedamigutamotaneru.pdf
    • https://jecoexports.com/ckfinder/userfiles/files/47244682958.pdf
    • http://shepardinteriordesign.com/rw/upload/file/73774384411.pdf
    • http://hotelborgodeipoeti.com/userfiles/files/gosinagul.pdf
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/aa5bd09435fc8bee0e2b1ef99d64f8ce/17224531136.pdf
    • https://kheops-so.fr/ckfinder/userfiles/files/77907919598.pdf
    • https://tectrongim.com/uploads/files/mukifewowexoxonejodir.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=crazy+rich+asian+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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dc79.bin
f29ae38521065c2fa58e54ed2ba51d1f66866611af7d48edf687b966b3d115b8
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC79 19324 bytes
font_01_sfnt_off00010f02.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F02 16792 bytes
font_02_sfnt_off00012719.bin
2bcddc4e50012d1dd0f607506aaa90793ec37c2edab7ae55997e53e4e0904362
pdf-font-stream PDF embedded font (sfnt) at offset 0x12719 10524 bytes