Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a4a91463519a749…

MALICIOUS

PDF

88.5 KB Created: 2021-06-26 22:14:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 59ca72808f919564dbbfbc2576d2a6d1 SHA-1: d893caaf658e6394e5f85a27b5064cb42f7c9e99 SHA-256: 4a4a91463519a749d10b42f6bf64f559af5621f21496c50eb6aa062d79ce7f9d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains embedded JavaScript and numerous URLs, many of which point to compromised CMS uploads or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a deliberate attempt to create a link farm, likely to manipulate search results or redirect users to malicious sites. The embedded JavaScript and the nature of the URLs suggest an intent to deliver a secondary payload or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • 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.
  • 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://cructi.ru/uplcv?utm_term=english+grammar+tenses+exercises+with+answers
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085a367ddfc3---vorosubirajobuxunasab.pdf
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/d54d0d2fb8fa4a3cbdef53786610ad55/peterozazaxidik.pdf
    • https://cambodiadriverservice.com/userfiles/file/19231436186.pdf
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/644f042eaa220f34cd3fd7ebd80a57f2/wesizudebibomosegeg.pdf
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/lod0349a8mroo7266t1ho9c9pc/8823440986.pdf
    • http://themultifold.com/wp-content/plugins/super-forms/uploads/php/files/uu5a7bppbquhhctjqufq90vkb3/65256522572.pdf
    • http://nextgenship.net/upload/file/20210522162168317768.pdf
    • http://asupuro.com/upload/save_image/files/sinexokokimomup.pdf
    • https://alianzatours.com/imagenes/file/46430692692.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160767d41669db---38642704932.pdf
    • http://whalesart.com/uploadfile/file///2021061414524890.pdf
    • https://amursvoidom.ru/media/files/25599157779.pdf
    • http://hotspot-usa.com/js/upload/files/rinipugubajanelej.pdf
    • http://toastwarenhuis.nl/app/webroot/files/userfiles/files/10540322496.pdf
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d1557b1333---58238611861.pdf
    • http://hysansam.com/fckeditor/userfiles/image/dodukukoko.pdf
    • https://envomask.com/wp-content/plugins/super-forms/uploads/php/files/7b46c4f2cdcc08b3a54e3604852fabb8/zujosomelosudazeburosadi.pdf
    • https://beyondpins.com/calisma2/files/uploads/laxifavurebekopedan.pdf
    • http://gourmethousemacau.com/UploadFilesfile///vororanuker.pdf
    • https://www.webplease.it/wp-content/plugins/super-forms/uploads/php/files/00na04gd1kfu0dscddkcmc9egg/gubufibezodineriv.pdf
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/qei3ae2l6qbdolg7a5u3e7e3fs/39356678447.pdf
    • 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_off0000f53b.bin
b4108ab04ac10c661c1f4682ed432abc3b903b61db2e7f403dffe6611ad293d5
pdf-font-stream PDF embedded font (sfnt) at offset 0xF53B 10728 bytes
font_01_sfnt_off00010db7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10DB7 16792 bytes
font_02_sfnt_off000125c9.bin
2caacf7f0a8f26094308dd0fc795e6f4a847b105fac9ebc1a54a204584d53a77
pdf-font-stream PDF embedded font (sfnt) at offset 0x125C9 17848 bytes