Malicious PDF — malware analysis report

Static analysis result for SHA-256 4cb57a71a63f0cf9…

MALICIOUS

PDF

85.8 KB Created: 2021-09-09 09:49:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 8c3dc582c356fe9293e2a59f5c0f79b9 SHA-1: 5686b370898d5a10683ea83a55810bc25f3558c7 SHA-256: 4cb57a71a63f0cf9f9ec7531449b940e66af3463249a4b53341d86cb8c52ef20
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document is designed to host numerous links on disposable domains, likely to redirect users to malicious content. The embedded URLs, despite some being marked benign, contribute to the overall suspicious nature of the document's intent to lead users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://sostrevalli.it/userfiles/files/sevew.pdf In PDF document text
    • http://atenngo.com/admin/sites/site/documents/sibet.pdfIn PDF document text
    • http://bhk-aindling.com/userfiles/files/79530069881.pdfIn PDF document text
    • http://t-p-fortune.com/userfiles/file/52995399571.pdfIn PDF document text
    • https://jackinthegymtpe.com/uploads/files/202109050445423747.pdfIn PDF document text
    • https://promise-land.com/upload/file/kolalovomonoletaw.pdfIn PDF document text
    • https://sportuna.be/ckfinder/userfiles/files/63426572514.pdfIn PDF document text
    • http://latiendasegura.com/contable_prueba/userfiles/file/5127830252.pdfIn PDF document text
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16134eb3b0ba83---84544169082.pdfIn PDF document text
    • http://billsky.ee/files/file/zuxekozoxikemu.pdfIn PDF document text
    • http://erodiertechnik-wenzel.de/userfiles/file/wenedaroxofeneti.pdfIn PDF document text
    • http://studioriboldi.eu/userfiles/files/13243203456.pdfIn PDF document text
    • http://secoinblock.com/upload/files/71789900763.pdfIn PDF document text
    • https://xn--hjrnskadeakademien-mtb.se/userfiles/file/96600923117.pdfIn PDF document text
    • https://tomas-music.com/contents/files/58262848567.pdfIn PDF document text
    • https://abcelectricalonlineshop.brilliantwebtech.com/userfiles/files/47412543417.pdfIn PDF document text
    • http://ferrocom-spb.ru/userfiles/files/21074132175.pdfIn PDF document text
    • https://sinaia-vik.com/admin/fckeditor/editor/filemanager/connectors/php/file/zuwewuvesisamaresawi.pdfIn PDF document text
    • http://www.zdravotechnika.com/ckfinder/userfiles/files/fufosomuvalejobupur.pdfIn PDF document text
    • http://yugreat.com/filespath/files/20210905195805.pdfIn PDF document text
    • http://batiment-tunisie.com/userfiles/file/95353732063.pdfIn PDF document text
    • http://www.polni.si/Images/files/57938896329.pdfIn PDF document text
    • http://greensketch.in/userfiles/file/dizivonukijobu.pdfIn PDF document text
    • https://turbooto.vn/upload/files/xibinosekoxa.pdfIn PDF document text
    • http://orzo.cz/uploaded/files/masofemisojafim.pdfIn PDF document text
    • http://lblussana.it/images/file/74805395263.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=best+android+gamepad+mapperPDF 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_off0000e75e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE75E 18824 bytes
SHA-256: a88b2374eb806e24a00fc749b530f89032c2fe40eb8850739af1db9b4225b17e
font_01_sfnt_off000118a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118A4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000130bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130BB 10740 bytes
SHA-256: 968d5c8c9fb8241e0acf4b6a627999e77af1ee0bdbbe2a5be5217782b41ebc2b