Malicious PDF — malware analysis report

Static analysis result for SHA-256 3abba749cfa6e38f…

MALICIOUS

PDF

104.3 KB Created: 2021-09-11 22:29:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 613b4aba1a8688e55705f51b315ab440 SHA-1: 73d6feaa82a97ce5e92d8d13ed5727745803397e SHA-256: 3abba749cfa6e38f84d55e4c5ff8aa916b510795f370d1fd3b0f6444e2b3af81
214 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1539 Steal or Harvest Credentials T1027 Obfuscated Files or Information

This PDF file was flagged by ML classifiers and ClamAV as malicious, exhibiting characteristics of a phishing and credential harvesting campaign. The embedded JavaScript and the document's instructions to disable security software and provide a one-time code strongly suggest an attempt to bypass security measures and steal user credentials or session tokens. The numerous external links, many pointing to PDF files on distinct hosts, indicate a link farm designed to obscure the true malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Security software disable instruction high SE_SECURITY_BYPASS
    Document instructs the user to disable antivirus or security software — unusual for ordinary documents and high-risk in an unsolicited file
  • MFA / one-time-code harvesting lure high SE_MFA_LURE
    Document asks for a one-time code, authenticator approval, or MFA confirmation — consistent with credential phishing kits that steal session tokens or abuse multi-factor authentication
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://doctorchina168.com/upload/files/xawusuvasifojokuvakozake.pdf In PDF document text
    • http://tw-jia.com/uploads/files/202109012217036693.pdfIn PDF document text
    • https://freshchannels.com/home/sites/freshchannels/public_html/ckfinder/userfiles/files/pobowafexo.pdfIn PDF document text
    • http://kite-surf.sk/files/6171724854.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/95321677312.pdfIn PDF document text
    • http://www.msjcongregation.org/www/js/ckfinder/userfiles/files/68313693590.pdfIn PDF document text
    • http://www.de.ruben.pl/ckfinder/userfiles/files/jonifak.pdfIn PDF document text
    • http://psychologkmalinowska.pl/ckfinder/userfiles/files/lejepaduzapipukapimubub.pdfIn PDF document text
    • http://baltic-rt.ru/ckfinder/userfiles/files/1252394973.pdfIn PDF document text
    • https://isagrinio.gr/userfiles/43837346286.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/fizavixivowubitevezotabok.pdfIn PDF document text
    • https://trickapotisk.cz/webpagebuilder/ckfinder/userfiles/files/58593161421.pdfIn PDF document text
    • https://remont-bez-zabot.ru/files/file/976032595.pdfIn PDF document text
    • http://a9188.com/upload_files/art_files/files/20210906_162920.pdfIn PDF document text
    • http://isotech.si/uporabnik/file/79993613181.pdfIn PDF document text
    • https://heart-calligraphy.com/uploads/files/202109011727351346.pdfIn PDF document text
    • https://sunriseinnjasper.com/nbloom/fckuploads/file/44227070431.pdfIn PDF document text
    • http://argol-editions.fr/userfiles/file/84142219910.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1612f9d203aacf---poxak.pdfIn PDF document text
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/4b30270a7e757ded9b71cf5f6c2ba51a/35749994803.pdfIn PDF document text
    • https://resttour.com/images/userfiles/files/fekodegafe.pdfIn PDF document text
    • http://xn----7sbev0bhje.xn--p1ai/images/news/file/79201756370.pdfIn PDF document text
    • https://webmakler.org/userfiles/file/8231104783.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=mi+account+unlock+with+unlock+codePDF link annotation
    • 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_off00012b7a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B7A 10472 bytes
SHA-256: cf84a48044b1bb5afbdea14d695a07d41b22b1519b8dce4b2c6458830df853c0
font_01_sfnt_off0001433d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1433D 21096 bytes
SHA-256: 1491e099bc5e0ce89e9b4ad323d38389aba44de7878a80af7aa36edf493c5c42
font_02_sfnt_off00017b7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17B7D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1