Malicious PDF — malware analysis report

Static analysis result for SHA-256 dea4b601e83ae585…

MALICIOUS

PDF

80.8 KB Created: 2021-10-07 18:12:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: efefacfd986bc0cf494f4430dfe668f7 SHA-1: 02ce6fea3b989295c054ec4ec705c1363964b7b6 SHA-256: dea4b601e83ae58570e3687f1c3357c28a2236947ef00ec398d48ad3c4b604af
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected by ClamAV as Pdf.Phishing.Trojan and an ML classifier flagged it as malicious. Heuristics indicate it functions as a link farm, with numerous URLs pointing to compromised CMS uploads and disposable hosting. The embedded URLs, such as 'https://philabc.ru/uplcv?utm_term=leaving+an+apartment+letter', suggest a lure to trick users into clicking through to potentially malicious content. No scripts were extracted, but the PDF structure and URL patterns are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 https://philabc.ru/uplcv?utm_term=leaving+an+apartment+letter PDF link annotation
    • https://www.allduniv.ac.in/ckfinder/userfiles/files/43345611758.pdfIn PDF document text
    • https://greenlakepaint.com/ckfinder/userfiles/files/29279868256.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/8c38f4f9e82001c556e0fde64a3ceb1c/45680543637.pdfIn PDF document text
    • http://zhongjiukeji.com/upload_fck/file/2021-9-23/20210923162027940286.pdfIn PDF document text
    • http://space-edge.com/upload/files/kevujelo.pdfIn PDF document text
    • https://watertorens.nl/userfiles/file/femekagona.pdfIn PDF document text
    • http://pobierzplik.pl/uploads/files/zined.pdfIn PDF document text
    • http://rrbrentacars.com/files/others/35512004040.pdfIn PDF document text
    • http://coumert.com/images/file/tokekigut.pdfIn PDF document text
    • http://s8radziejowice-paszkow.pl/userfiles/file/jobeku.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/a8891c3b456d6d6d66dfc52abed47fa3/8794377496.pdfIn PDF document text
    • http://e-photo.lv/ckfinder/userfiles/files/vobewunajafisu.pdfIn PDF document text
    • http://tourbusan.net/FileData/ckfinder/files/20210909_D8CAB23E97C0B2AD.pdfIn PDF document text
    • http://gandolfiarchitetti.com/userfiles/files/9972499880.pdfIn PDF document text
    • http://artstudiodesign.it/userfiles/files/61012691162.pdfIn PDF document text
    • http://cosonhuath.com/hinhanh_fckeditor/file/gixufulutamawawupa.pdfIn PDF document text
    • http://proleague.dk/userfiles/file/lugenojoteluzilijubi.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/242d9e0ad21bd312b6836bb8fe4f8fef/ranitavugobetisu.pdfIn PDF document text
    • http://enricobarraco.com/files/risabenegisivuz.pdfIn PDF document text
    • http://speaklifeiamgreatness.com/files/files/45734229799.pdfIn PDF document text
    • http://tuanlongland.com/upload/files/sapegaxijevumo.pdfIn PDF document text
    • https://keyword-lda.pt/site/upload/file/76881206039.pdfIn PDF document text
    • http://clubselectionvoyages.net/images/file/76536482217.pdfIn PDF document text
    • https://sokolzgierz.pl/web/uploads/files/gexapusulivefasib.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_off0000d96e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD96E 17672 bytes
SHA-256: 442a546db4bd189a2390d84bbe00e8424438bf2657af16f629423568cb8b2fd4
font_01_sfnt_off000106b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106B2 10332 bytes
SHA-256: d53928730d7e5fb6494749184f46d40a9d840a79cb2e62cae60965a067ff5db9
font_02_sfnt_off00011ded.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1