Malicious PDF — malware analysis report

Static analysis result for SHA-256 a71d9c312b9c13f9…

MALICIOUS

PDF

75.3 KB Created: 2021-09-13 02:52:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 208d141d9f68b6a0e0cd85af360bdc6f SHA-1: 9cc004a84542149707af7d8d4e7c779060b37473 SHA-256: a71d9c312b9c13f9e0d45f68b8e98e52714f4bb2afd8d72763cbeaff696b1f28
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, embedding a large number of URLs, many of which point to unknown or potentially malicious domains. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further suggests a deliberate attempt to create a deceptive web presence.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/ca00fe9d802d69a6bfed3aac2a5845dc/japoxupago.pdf In PDF document text
    • http://savvyais.com/userfiles/file/92141635504.pdfIn PDF document text
    • http://seoulmenu.com/uploads/files/duvivibodipejonabinu.pdfIn PDF document text
    • http://neoneophytou.com/ckfinder/userfiles/files/putomuwen.pdfIn PDF document text
    • https://mhreng.com/userfiles/file/4247850281.pdfIn PDF document text
    • http://labonscafe.com/userfiles/8657032285.pdfIn PDF document text
    • https://rrrc.us/userfiles/file/pirajeku.pdfIn PDF document text
    • https://ijp2.com/contents/files/nujazufolubekuj.pdfIn PDF document text
    • https://rizecanreklam.com/images/file/29193162558.pdfIn PDF document text
    • https://pvcmikser.com/upload/files/28767542026.pdfIn PDF document text
    • https://shreegroupco.com/userfiles/file/8996919758.pdfIn PDF document text
    • http://cowmoo.org/ckfinder/userfiles/files/volekudasijakaxol.pdfIn PDF document text
    • http://fpole.ru/sadm_files/3144288098.pdfIn PDF document text
    • https://kapefashion.com/files/files/53443225317.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d35e9ab2e3---pejojefujowemojagifaja.pdfIn PDF document text
    • http://conblocmanado.com/pics/file/95756762757.pdfIn PDF document text
    • http://busankid.com/webfiles/board/file///43195319388.pdfIn PDF document text
    • http://studiospazioambiente.it/userfiles/files/2281863231.pdfIn PDF document text
    • http://mtsskzy.com/userfiles/file/81839734864.pdfIn PDF document text
    • http://okna-kursk.ru/page_edit/_samples/userfiles/files/3955879119.pdfIn PDF document text
    • https://mkontakt.com/dat/file/20024612054.pdfIn PDF document text
    • https://xulynuocphangiathinh.vn/images/pic/file/2031532255.pdfIn PDF document text
    • https://champion-osk.pl/userfiles/file/kafakowiloloma.pdfIn PDF document text
    • http://amkchem.com/upload/files/tometadalomuwewela.pdfIn PDF document text
    • http://worldnaturalfood.com/image/upload/File/81055202669.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=how+to+get+rid+of+duplicate+apps+on+androidPDF 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_off0000bcbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBCBD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d4cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4CF 19388 bytes
SHA-256: c2e274c8cf791d4cb241f5420974c331b879f62099feedb2c466117ca549fb09
font_02_sfnt_off00010657.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10657 10972 bytes
SHA-256: b2835bd61e16003934eeffe10188e0e30a2f4b1659c3fda507598edeb790f98a