Malicious PDF — malware analysis report

Static analysis result for SHA-256 f10ea4683133a988…

MALICIOUS

PDF

82.9 KB Created: 2021-09-11 06:26:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: bd04e7679a55e27ac00326846444c542 SHA-1: b87e888e173d6a6e62873c68391c633089dabfbf SHA-256: f10ea4683133a9886e5ed2e8e1c03e85207bd082417d72b4d70fe0ceae98ccfc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains a link farm, with numerous URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this, suggesting the document is part of a campaign to leverage search engine optimization and compromised websites for malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://krisoc.ru/uplcv?utm_term=how+to+find+junk+files+in+android
    • https://dynasty888.com/image/files/20210901_160252.pdf
    • http://abwplazaview.com/uploads/files/sivegobuxulobirafi.pdf
    • http://djk-winkel.de/images/uploads/file/11377865266.pdf
    • https://dveropolis.ru/upload_picture/jatidawijivokemora.pdf
    • http://hibertek.com/image/files/20210910_220359.pdf
    • http://safarang.com/basefile/files/kaxodemoxe.pdf
    • http://computerdoki.hu/user/file/zisezixolurut.pdf
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/h22t4k0nud4dlfs29bql8qaits/72639288215.pdf
    • https://www.igescanada.com/ckfinder/userfiles/files/91285563271.pdf
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/161337e9b40fcd---59038186721.pdf
    • http://slesnick.net/userfiles/files/45540510169.pdf
    • http://batterseataxi.com/survey/userfiles/files/jumifatadonogezab.pdf
    • https://h16hr15k-h19hr37urn.com/contents/files/xozunimonefegosokisebem.pdf
    • http://maybomnuocdanang.com/uploads/image/files/49659566884.pdf
    • http://irina-beha.com/ckfinder/userfiles/files/nawokigajopiwopuk.pdf
    • http://tt-ural.su/admin/ckfinder/userfiles/files/tagalutixufigudoju.pdf
    • http://kanoonkaraj.ir/dbmanager/filebank/htmlgallery/file///dugovifif.pdf
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613897902eba6---xezasawizakewevoxu.pdf
    • http://www.bluefashion.cz/ckfinder/userfiles/files/jexesuba.pdf
    • http://puisan.ru/uploads/file/92474376954.pdf
    • http://motovelo-nmsk.ru/userfiles/file/57190821717.pdf
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/0nnkkssm6f5m981288lcmro898/notujo.pdf
    • http://chekeeh.ir/basefile/chekeehir/files/sabirake.pdf
    • http://kssi.ir/public/userfiles/file/4117259177.pdf
    • http://www.supair-lux.hu/ckfinder/userfiles/files/beguvimatamukekav.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_off0000dd15.bin
761fb78d33ec95f795cf0cf0cde36e550c446f602710206fce7c863db7af5f5d
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD15 10748 bytes
font_01_sfnt_off0000f5e4.bin
0a87ce85e7df7adf5c050cc706a012bfeef1ed9a0f01e3433570881dafa70738
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5E4 18568 bytes
font_02_sfnt_off00012608.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12608 16792 bytes