Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7b255dea93233a0…

MALICIOUS

PDF

77.7 KB Created: 2021-09-13 09:19:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 37f485c10e89d84f237cf9ebe0ed5f17 SHA-1: bc2a4575b0b42f0e49fbe6512c13b7e0c7b94e26 SHA-256: b7b255dea93233a031cf977ba4e0e7bd1d950077b87109db0e31fb2bd7b3731e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, with many pointing to potentially malicious domains, and is flagged by ML classifiers and ClamAV as malicious. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicates a tactic to obscure the true destination by using a large number of links on disposable hosting. While no scripts were explicitly extracted, the nature of the embedded links suggests a phishing or malware distribution attempt.

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 http://aybar-gallery.com/userfiles/files/dopidawefiwelinafi.pdf In PDF document text
    • http://iact2001.com/userData/board/file/xasifadip.pdfIn PDF document text
    • http://kwiatmetal.pl/userfiles/file/bidodusebedapat.pdfIn PDF document text
    • https://www.totspotdaynursery.co.uk/ckfinder/userfiles/files/metukuzagasejiwavujijotik.pdfIn PDF document text
    • https://trompis-tondschungel.de/userfiles/file/matinurumesawevi.pdfIn PDF document text
    • https://phuketwebstudio.com/ckfinder/userfiles/files/24218274768.pdfIn PDF document text
    • https://razredna-nastava.net/files/81314998689.pdfIn PDF document text
    • http://www.poliklinika-hb.cz/userfiles/file/gusakitejunokipi.pdfIn PDF document text
    • https://fotojursa.cz/userfiles/file/75690119298.pdfIn PDF document text
    • http://op-gold.com/ck_image/files/nojoponiwuvitiji.pdfIn PDF document text
    • http://lubrifianti-auto.ro/files/file/48799347946.pdfIn PDF document text
    • http://paramountswimwear.com/userfiles/files/42391651920.pdfIn PDF document text
    • https://bunian-co.com/other_files/File/51432592020.pdfIn PDF document text
    • http://e5tbr.alruaa.com/ckeditor-ckfinder-integration/uploads/files/17177468910.pdfIn PDF document text
    • http://hissekurban.com/resimler/files/tinilewajudadajaje.pdfIn PDF document text
    • http://edu-family72.ru/content/images/uploads/file/19128465528.pdfIn PDF document text
    • http://tunglamgarden.com/images/fck/file/54946188760.pdfIn PDF document text
    • http://www.tomasjelinek.com/img/pub/file/61460751596.pdfIn PDF document text
    • https://pima-alarms.eu/slicice/file/jigixejevipejejujulifewik.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/161316ad163782---37019517061.pdfIn PDF document text
    • http://kingkady.cn/uploadfile/files/jasojebovitonuzik.pdfIn PDF document text
    • http://scarpatti.com/files/guditidinutibeboxirus.pdfIn PDF document text
    • http://gibisch.biz/files/files/93609661453.pdfIn PDF document text
    • https://kamhosting.nl/ckfinder/userfiles/files/tipepokakun.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=st+luke%27s+barry+road+primary+carePDF 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_off0000cc18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC18 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e42f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE42F 11128 bytes
SHA-256: 86777222ba49e7d8bb4df7c28ef924b02d73d9b424263887e8ea66a86ae868f0
font_02_sfnt_off0000fe07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE07 16512 bytes
SHA-256: 062c7a8bc148cbee7f2bd8c6ef24ffb960a49c096e6b17484184f2a3c3be6640