Malicious PDF — malware analysis report

Static analysis result for SHA-256 d37a379ccac20b1e…

MALICIOUS

PDF

82.6 KB Created: 2021-09-19 21:08:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 71ea85fed986da396e23a8e0f11a2785 SHA-1: 8c94067fc71e6dbe354bfca56ee0d350fefb41c7 SHA-256: d37a379ccac20b1e301b722f9440d6006a76814c57dc3f13969db5a9ad1c28cf
214 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1140 Deobfuscate/Decode Files or Information

The PDF contains embedded JavaScript and multiple external URLs, indicating it is designed to lead the user to malicious content. Heuristics suggest it acts as a lure for password-protected archives or MFA harvesting, consistent with phishing tactics. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to download and execute a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://wastran.ru/uplcv?utm_term=how+to+override+pattern+lock PDF link annotation
    • https://yomadesign.com/userfiles/Proj_Name/files/91847315880.pdfIn PDF document text
    • http://muacuoi.vn/Pictures/files/45991648548.pdfIn PDF document text
    • http://naviway.su/upload/files/37258861284.pdfIn PDF document text
    • http://protectakoteasia.com/ckfinder/userfiles/files/33685385473.pdfIn PDF document text
    • https://sskundal.com/userfiles/file/fupegabozule.pdfIn PDF document text
    • https://eastoncn.housemember.com/uploads/files/nebexajexixedoxokofifub.pdfIn PDF document text
    • https://www.iieng.org/editor/ckfinder/userfiles/files/noselipatewolegenixexaba.pdfIn PDF document text
    • http://wangguanhardware.com/userfiles/file/52915774997.pdfIn PDF document text
    • https://zemtechnika.lt/public/site/0files/42519453605.pdfIn PDF document text
    • http://chothuethietbi.info/img/files/89025260059.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161417e163b1ac---zuzegosirogupubor.pdfIn PDF document text
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/1796196864.pdfIn PDF document text
    • http://gameometria.com/assets/ckfinder/core/connector/php/uploads/files/33183345404.pdfIn PDF document text
    • http://wxbeimei.cn/upload/ckimg/files/202109130303067606.pdfIn PDF document text
    • http://colorfusion.us/admin/images/file/25474927618.pdfIn PDF document text
    • http://wxeina.com/userfiles/files/buvafevovamuluvumiko.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/6e16b42dcf47a14c713f2b87df1f7a68/24545253788.pdfIn PDF document text
    • http://vegman-kzn.com/ckfinder/userfiles/files/8942287454.pdfIn PDF document text
    • http://bernendorf.ru/userfiles/file/wunupavuz.pdfIn PDF document text
    • http://laarakkers.com/ckfinder/userfiles/files/7648726824.pdfIn PDF document text
    • http://skyrunarser.com/js/fckeditor/editor/filemanager/connectors/php/connector.php/upfiles/file/210917150904684011azcgam.pdfIn PDF document text
    • http://eot.mn/uploads/userfiles/files/javixowetiro.pdfIn PDF document text
    • http://esangsok.com/upfile/files/35527610089.pdfIn PDF document text
    • https://mayersoffice.com/userfiles/file/musabalojakaz.pdfIn PDF document text
    • http://igigeothermal.jp/userfiles/file/73430844934.pdfIn PDF document text
    • https://stancijanegrin.com/UserFiles/files/bujujegolaranej.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_off0000de80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE80 10572 bytes
SHA-256: b9238f1a7fd676a21d60fc2b5672786c2743d398374c7f20ba951ea88daff59d
font_01_sfnt_off0000f6be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6BE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010ed0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10ED0 18012 bytes
SHA-256: cce5055d9a295f458afbae93749e15dc542ee342964015f1caac5ae780544cf0