Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4697ac80f9d5051…

MALICIOUS

PDF

75.2 KB Created: 2021-10-08 01:34:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: b8c15cb562ce0005376a5cb95893aa40 SHA-1: 693b4bec9cff06614e1abc77222167d5f9211a77 SHA-256: f4697ac80f9d505107972c65ba2501a654da61db572121f429f4a8dcfb2a5ebe
126 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Numerous external URIs were extracted, suggesting the PDF acts as a lure to external malicious sites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this, indicating a large number of links on disposable hosting, a common tactic for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://coretry.ru/uplcv?utm_term=land+surveying+services+inc PDF link annotation
    • https://sunarchegypt.com/userfiles/file/67047563943.pdfIn PDF document text
    • http://superlitefan.com/uploads/files/81863296842.pdfIn PDF document text
    • http://101-games.ru/images/uploads/files/dedol.pdfIn PDF document text
    • http://4yoga.by/pics/files/48335213840.pdfIn PDF document text
    • https://vsevolozhsk.mebel18.com/uploads/files/2093361766.pdfIn PDF document text
    • http://ejmk.com/ej/upload/files/1737847072.pdfIn PDF document text
    • http://udmvdpo.ru/images/files/51772232928.pdfIn PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/16132197300ce2---44774640920.pdfIn PDF document text
    • http://librojuridico.com/aym_images/files/wutumojepalifiluvuron.pdfIn PDF document text
    • http://cjmfgx.morefriendship.com/upload/files/21544329482.pdfIn PDF document text
    • http://bifruit.mk/ckfinder/userfiles/files/fufisobidix.pdfIn PDF document text
    • http://canadianartistic.com/userfiles/file/wififorevidapogati.pdfIn PDF document text
    • http://2018.letnifestiwal.pl/ckfinder/userfiles/files/68982690107.pdfIn PDF document text
    • https://psychotherapie-coeppicus.ch/userfiles/files/vifulujukefefisixarunupu.pdfIn PDF document text
    • https://www.multilandtours.com/assets/ckfinder/userfiles/files/27136908065.pdfIn PDF document text
    • http://vp-dmsh.ru/admin/ckfinder/userfiles/files/67460410499.pdfIn PDF document text
    • https://baruipur.org/ckfinder/userfiles/files/27366849762.pdfIn PDF document text
    • http://angerdress.store/ckfinder/userfiles/files/37889824641.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1613f7b8a112bb---11240816776.pdfIn PDF document text
    • https://flavio-tonon.it/public/file/volev.pdfIn PDF document text
    • http://renovfab-menuiserie.com/userfiles/file/gedotaguvekapimumigol.pdfIn PDF document text
    • http://itagqatar.zajeltel.com/itag/file/files/novizikavakawirenox.pdfIn PDF document text
    • http://dlzhrjd.com/images/uploadfile/files/kotarelexenunegi.pdfIn PDF document text
    • http://gzafjc.com/uploadfile/files/85719834113.pdfIn PDF document text
    • http://mezon.jp/userfiles/file/pilududiruzuv.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_off0000c356.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC356 10516 bytes
SHA-256: 06127ac27705f69f96f40c3531906452968cbca3de8103f78d29af7ce6662f1f
font_01_sfnt_off0000db32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB32 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f344.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF344 17044 bytes
SHA-256: c4c2fd49bd08ef3d62f74d6896a5c1b2d30b29cce07514398456339e89f65e34