Malicious PDF — malware analysis report

Static analysis result for SHA-256 8259066cc504a8eb…

MALICIOUS

PDF

67.6 KB Created: 2021-10-02 11:44:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: c38c565effa67c6adba854bb660433dd SHA-1: 868cac6f089f0d7b51c319c7b83c69d7873e4959 SHA-256: 8259066cc504a8ebc37e889483c3bb2cd6c3e78c790f3cfeb1f784f71a37b5ce
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file identified as malicious by ClamAV and an ML classifier. It contains embedded JavaScript, which is a common technique for executing malicious code within PDFs. The document also features a large number of external URLs, many hosted on disposable domains, indicating a link farm designed to redirect users to potentially harmful content. The presence of embedded JavaScript and numerous external links strongly suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://smidgel.ru/uplcv?utm_term=apk+ps3+android PDF link annotation
    • https://spvi.cn/filespath/files/20210901192903.pdfIn PDF document text
    • https://tailormade-sales-marketing.com/userfiles/file/30545982705.pdfIn PDF document text
    • https://galerieportelouise.be/userfiles/files/pifibeneva.pdfIn PDF document text
    • https://toolsatool.com/userfiles/files/89435249072.pdfIn PDF document text
    • http://flairpens.ru/uploads/files/rarisuwivivexibuvomukixis.pdfIn PDF document text
    • https://medbillings.us/lightspeedweb1/file/xubowujopawaxifudepi.pdfIn PDF document text
    • http://sysquare.com/UserFiles/files/75736817670.pdfIn PDF document text
    • http://zehanbiopharma.com/upload/files/gogetorajigitisigu.pdfIn PDF document text
    • http://ameshamagazine.com/js/upload/files/jefuwokisofuvobanat.pdfIn PDF document text
    • https://tonmathunglan.vn/upload/files/12035546190.pdfIn PDF document text
    • https://jck.ro/userfiles/file/dinovojarisog.pdfIn PDF document text
    • http://studioboscono.it/userfiles/files/30243773402.pdfIn PDF document text
    • https://jmcoverseaspvtltd.com/uploads/files/soxogarunasonepej.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161354bff0607e---87961544319.pdfIn PDF document text
    • https://afmiletisim.afmiletisimajansi.info/resimler/files/407004670.pdfIn PDF document text
    • http://dymenahealthcare.com/upload/fckeditor/file/mizasowazuferixeluxidik.pdfIn PDF document text
    • https://tonymusic.se/UserFiles/files/8829016446.pdfIn PDF document text
    • https://gangwontaxi.com/FileData/ckfinder/files/20210908_29AFA7EB24F39DDE.pdfIn PDF document text
    • http://www.domplit2006.ru/ckfinder/userfiles/files/xojokejufuvimapejimekufom.pdfIn PDF document text
    • https://tramtron.vn/uploads/files/files/8253554670.pdfIn PDF document text
    • http://www.keizerco.nl/userFiles/file/5324057342.pdfIn PDF document text
    • https://byocamacho.com/ckfinder/userfiles/files/fetoli.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_off0000ac1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAC1F 15036 bytes
SHA-256: 09081fac66f4e3027d2d1df41e9c26ebd6ae99eb6c958c18acbb92ff4de5bccf
font_01_sfnt_off0000d20a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD20A 10352 bytes
SHA-256: 85bc15a7f389193ada5a58ca09b558de66ce1cbe6f497bd4cd894d48f066b767
font_02_sfnt_off0000e98a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE98A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1