Malicious PDF — malware analysis report

Static analysis result for SHA-256 39da62f3dca30d7a…

MALICIOUS

PDF

94.6 KB Created: 2021-06-29 09:43:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b1d98e6961e768c89e4f304212cce136 SHA-1: 441d7a6b8779beb6d275a97b6ecf7df38e46246e SHA-256: 39da62f3dca30d7ae4ca61b7076fc84c75319b857c74867690b79c5b9ce6d9f6
256 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1539 Steal or Harvest Credentials

This PDF document was flagged by a machine learning classifier as malicious and exhibits critical heuristics for a recovery secret or private key harvesting lure. The document likely aims to trick users into revealing sensitive information such as private keys or backup codes, which could lead to account compromise or financial loss. Multiple URLs pointing to compromised CMS upload storage and disposable hosting were extracted, suggesting a phishing infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

Heuristics 8

  • Recovery secret / private key request critical SE_SECRET_RECOVERY_LURE
    Document requests recovery phrases, private keys, backup codes, or saved passwords. Requests for these secrets in a document are high-risk.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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
  • 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://tavio.ru/files/file/85075081548.pdf
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1607da69932781---gomogan.pdf
    • http://ned.ru/uploads/files/wuwuluvupuwepunot.pdf
    • https://www.straightmyteeth.eu/wp-content/plugins/super-forms/uploads/php/files/2f00993b912449ef0c2cff67524355bb/nukilunepokimogokugagirig.pdf
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/7f4fcee78b549446990834940c3e8615/79965980620.pdf
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/7683fed049baf7aea4f5a7a4063ef6ab/tanovalepeneruvimaxi.pdf
    • http://allycatering.com/userfiles/70054101328.pdf
    • http://zonweringnederland.com/ckfinder/userfiles/files/jebadevovufabewaf.pdf
    • https://vntdc.com/upload/fck/file/5081982171.pdf
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608fa2d76fb98---rezukuri.pdf
    • http://asbazainville.org/userfiles/file/tofomexijulos.pdf
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/79v5cs5tfmqalq2ea2d8bujcl4/32587894117.pdf
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606ef56c5f3bb---salasedugikizugozisopoxej.pdf
    • http://ufnk.fr/app/webroot/files/file/72696548301.pdf
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089340c86dd2---7489422623.pdf
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/160cbef185dbbe---64411345487.pdf
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/ifg1u8uh0ejrmafg2hkfhoae27/91309113832.pdf
    • http://pnmanagementsolutions.in/uploads/lovane.pdf
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/5cc80092233bd21af97f6fb85ef0e34b/dusubapofu.pdf
    • http://studiogiamberardino.it/userfiles/files/30499958363.pdf
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a7ebc67b378---11851016937.pdf
    • https://mamap.in/ci/userfiles/files/58465738913.pdf
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095fef923898---revinuw.pdf
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160bbc6032a376---78841862249.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=different+types+of+cryptographic+keys
    • 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_off00010fb0.bin
dd11a8c121f6f8607418dbdae094173868d4125c59b0201526d433246ed1b46a
pdf-font-stream PDF embedded font (sfnt) at offset 0x10FB0 10920 bytes
font_01_sfnt_off00012905.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12905 16792 bytes
font_02_sfnt_off00014117.bin
b50e5207cb758f48cb57991c7cb89cc62729b6bd1c3c496adfd8e8687ef59c5a
pdf-font-stream PDF embedded font (sfnt) at offset 0x14117 16964 bytes