Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e0877271a103ce0…

MALICIOUS

PDF

87.0 KB Created: 2021-07-21 03:03:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6e08873d49bb40107e8ddf5af525fcfc SHA-1: f7779367a49578b35d0128210c246175af6133a5 SHA-256: 4e0877271a103ce04cfc41b95ba7ec08cee5b50c740e328fb7f8aa7272c04b25
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple compromised WordPress upload locations. The embedded URLs, such as http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b3438f62f21---nuwigujelubixopudono.pdf, are likely used to host or redirect to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b3438f62f21---nuwigujelubixopudono.pdf In PDF document text
    • http://www.misshandicap.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160748b5e3a54e---49752710142.pdfIn PDF document text
    • http://old.arcnet.org.tw/ckfinder/userfiles/files/pefabobikedok.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/96936033005.pdfIn PDF document text
    • https://avela.md/userfiles/file/lurubumadixuloxetep.pdfIn PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160f10f311b864---bipuboxijovep.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/f1438f758a720af3f97e057c36ead1bf/26103122918.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/cimej168o93fmjbt87al10oer1/15648933539.pdfIn PDF document text
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/acecff814d80aebbfa4bca69eff3f2f3/73568169687.pdfIn PDF document text
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a28b347d4b3---20766231824.pdfIn PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/mg6bomegdopiaefl97tickb2ji/61272646399.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b26f35da48e---benopezox.pdfIn PDF document text
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/jaum6fq36qtu7o37cvps0g883n/58428433558.pdfIn PDF document text
    • http://dianacb.cz/userfiles/file/95150195033.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/lqr1td4f0vmaeqhjaqhlgpv1t5/rutabusojimojutuvidesoli.pdfIn PDF document text
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c979c420363---gokabetegevigijebozetovi.pdfIn PDF document text
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606efba9c2c2a---fetefisa.pdfIn PDF document text
    • https://coevent.ru/upload/files/wisegogoxa.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/pp77f5oh798vklnl26dvvivkh1/jiduxominuxom.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/333a1fa39a8deb79419500f863f134ae/92661390158.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/winosajirogitadifivo.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/069f832f496e7602776184ca08e83edc/29345808687.pdfIn PDF document text
    • http://praguetransfer.com/files/file/46851625396.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a772b28fa80---daparizupisiwowed.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=baby+tooth+infectionPDF 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_off0000f40f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF40F 16556 bytes
SHA-256: 70f06223f07746287ecb8b93dcf4ad50269f5034378da136a5bceed2ade05c02
font_01_sfnt_off00011f2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F2E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013745.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13745 10428 bytes
SHA-256: db6283410858d6097a12557fd615366f8544cf7cfc262dfb94fee08dd797c509