Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c2f8711f6bc4b72…

MALICIOUS

PDF

76.9 KB Created: 2021-09-25 11:54:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 5b35f27ad85f9a8b3666ec3091588347 SHA-1: cca4315875b71999fc6d46a95c20f5df47625350 SHA-256: 4c2f8711f6bc4b7259abc133ec3ff9af2ac1b221baff0dcadba20ac555dde7db
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. The PDF contains numerous embedded URLs pointing to disposable domains, characteristic of a link farm designed to redirect users to malicious sites. While no scripts were directly extracted, the PDF structure and the presence of external URIs suggest an attempt to exploit vulnerabilities or deliver further malicious content. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly indicates the document's purpose is to host a large number of links on potentially compromised or disposable domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 https://wastran.ru/uplcv?utm_term=eac3+format+not+supported+mx+player PDF link annotation
    • http://pokorny-podlahy.cz/UserFiles/File/jumixijojopabegabowoguwik.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/161395299a1bd1---mewixujafogorulib.pdfIn PDF document text
    • https://jajugroup.com/ckfinder/userfiles/files/kazeximexuturesojevafe.pdfIn PDF document text
    • http://sineadstone.com/userfiles/file/22526366956.pdfIn PDF document text
    • http://dajia1.com/upfiles/editor/files/92947617232.pdfIn PDF document text
    • https://isleo.com/i_photos/file/28589571375.pdfIn PDF document text
    • https://tigapilar.com/upload/files/75717152410.pdfIn PDF document text
    • https://iphonerepairservice.nl/app/webroot/files/userfiles/files/gadigigo.pdfIn PDF document text
    • http://fueandhair.com/userfiles/files/12355187952.pdfIn PDF document text
    • http://boathousebrokerage.com/userfiles/file/lojavadivuvega.pdfIn PDF document text
    • https://palcev.ru/userfiles/file/36997284346.pdfIn PDF document text
    • https://tivirtual.com/userfiles/file/gilegagulilokevalosula.pdfIn PDF document text
    • https://creteservices.com/FCKeditor/userimages/file/48836372124.pdfIn PDF document text
    • http://athaj2.specialty-match.com/upload/files/6704307446.pdfIn PDF document text
    • http://zrdb-drogbud.pl/Upload/file/disejidofogugumi.pdfIn PDF document text
    • http://www.biharikft.hu/bihari-admin/ckfinder/userfiles/files/51251077236.pdfIn PDF document text
    • https://sistemagestiondpr.com/userfiles/file/ralol.pdfIn PDF document text
    • https://hojoairport.com/images/file/91459226552.pdfIn PDF document text
    • https://projektovanje.info/userfiles/file/xegutaxaxusanal.pdfIn PDF document text
    • https://bititechnika.com/uploads/file/11704555133.pdfIn PDF document text
    • http://vinhosnorte.com/images/files/xovet.pdfIn PDF document text
    • http://perfectionistpaintingnj.com/ckfinder/userfiles/files/38890951545.pdfIn PDF document text
    • http://xn--zb0by3yusal20ak5lcidnwigi.com/ckfinder/userfiles/files/1632522180.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/2kg7r3mta55se9f7rsf0b698bo/fukujesoxobawer.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_off0000bc41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC41 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d458.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD458 11160 bytes
SHA-256: 8d4e3b26037b69642b449f25da888beec7ae8a5e7940bd689b4ff5a1330e0070
font_02_sfnt_off0000ee87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE87 21224 bytes
SHA-256: 23173c7ec4fbe57ec76bc2bbe0964a22f7e9326c7f8b56bb1597602d5a9109d3