Malicious PDF — malware analysis report

Static analysis result for SHA-256 aaa87eec879ce5dd…

MALICIOUS

PDF

69.8 KB Created: 2021-10-02 18:14:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: e086108d3f7b5030fedef67b77f2919d SHA-1: 22dda9ccfb6dcc89f4bd8fcbf2832e8bd30d62e4 SHA-256: aaa87eec879ce5dd83197eb6da95ae122ff69bdaec4825a32b17e3eb1c473c44
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous embedded URLs pointing to external sites, suggesting it functions as a link farm or phishing lure. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM further supports this, indicating a strategy to distribute links across disposable hosting. No scripts were extracted, but the presence of external URIs and the overall detection profile strongly suggest a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://cructi.ru/uplcv?utm_term=new+day+beginning+quotes PDF link annotation
    • https://shiprapublication.com/uniformkontakt/userfiles/image/files/44428307693.pdfIn PDF document text
    • http://mywayrtk.info/userfiles/file/80092017772.pdfIn PDF document text
    • https://subded.org/userfiles/file/1087384577.pdfIn PDF document text
    • http://tmkb.org.tr/ckfinder/userfiles/files/42734622558.pdfIn PDF document text
    • https://teamcode.net/upload/files/91289475038.pdfIn PDF document text
    • http://sigmabhp.pl/userfiles/file/vekopivigavovuzaki.pdfIn PDF document text
    • http://integrotech.pl/zdjecia/file/rukafezijizetivesuv.pdfIn PDF document text
    • http://kanomax-nsk.ru/images/40695584936.pdfIn PDF document text
    • https://quangcaowebsite.vn/uploads/files/toritigimegoveniguvor.pdfIn PDF document text
    • http://nemeckystrakac.sk/editor_uploads/files/juridovomapulos.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/c2e2dfa6c6af28069d47dea2caecc588/32407740808.pdfIn PDF document text
    • http://hastensandbreakfast.nl/userfiles/file/nugeragituxetibojilil.pdfIn PDF document text
    • http://kooijobs.in/ckfinder/userfiles/files/totawexorikezojejokopexi.pdfIn PDF document text
    • http://malifer.hu/upload/file/98598823164.pdfIn PDF document text
    • http://www.tempshift.com/app/webroot/files/uploadimagesfile/xepawitogadubudokojel.pdfIn PDF document text
    • http://bakefruit.com/uploads/files/202109301218119133.pdfIn PDF document text
    • http://tlw.ro/UserFiles/file/bujetunazixirufusonavupod.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/161463e811b349---58240662832.pdfIn PDF document text
    • http://www.alex-vasilkov.ru/images/wisdom/file/24195696738.pdfIn PDF document text
    • http://puisan.ru/uploads/file/melawotinurogavalupesa.pdfIn PDF document text
    • http://indigobaby.eu/upload/files/5253231508.pdfIn PDF document text
    • http://plise.org/userfiles/file/69461930540.pdfIn PDF document text
    • https://cuacuonbentre.com/upload/files/rewolopuzudemun.pdfIn PDF document text
    • http://nuovojob.com/userfiles/files/ronufojub.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b1e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1E5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c9fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9FC 10840 bytes
SHA-256: 88e3f351d1d7743587e4ee43c7d89bd65b6cc1e524c5e8117b66015271ef240f
font_02_sfnt_off0000e2b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2B3 15400 bytes
SHA-256: 63ee2c469f453898904dbac988570bc6c427e2535cc8ff8db47aa10cc1d06689