Malicious PDF — malware analysis report

Static analysis result for SHA-256 cad331b4550f45be…

MALICIOUS

PDF

73.0 KB Created: 2021-09-19 02:07:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: c5a6a4faead5d3c592c3204b4230b381 SHA-1: 795f85fdbc101da07e03e81d19b45cd6d5c0b4f2 SHA-256: cad331b4550f45be8c7271ac0cb120fa037cb8a82977c862a1030658e73e6e7c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to disposable domains and are structured as link farms, a common tactic for phishing or malware distribution. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, suggesting the PDF's primary purpose is to redirect users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://xn----otbbfbbknchz.xn--p1ai/sadm_files/putazelexurunabo.pdf In PDF document text
    • http://24x7taazasamachar.com/assets/ckfinder/core/connector/php/uploads/files/73977233811.pdfIn PDF document text
    • http://jarosi.hu/files/file/57640811559.pdfIn PDF document text
    • http://isvpro.com/custom/files/3628246467.pdfIn PDF document text
    • http://www.weilandensemble.nl/ckfinder/userfiles/files/79313595379.pdfIn PDF document text
    • http://tnslib.tools/userfiles/files/mipabixesado.pdfIn PDF document text
    • http://kehlux.lu/userfiles/files/11183293374.pdfIn PDF document text
    • https://databaze-zdarma.cz/userfiles/files/62180285900.pdfIn PDF document text
    • https://libyamonitor.com/sites/all/libraries/ckfinder/userfiles/files/36626792190.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/58516e08ac8c2fa08ad7b5647f788236/2715226686.pdfIn PDF document text
    • http://blueview.nl/app/webroot/files/userfiles/files/nomotevexoxakamuti.pdfIn PDF document text
    • https://printjet.pl/pliki_user/File/43288192606.pdfIn PDF document text
    • http://jinshi66.com/uploadfiles/files/53924029719.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/gagoniwer.pdfIn PDF document text
    • http://businessnavigator.in/ckeditor/uploads/files/besaxogodaponoweronejo.pdfIn PDF document text
    • https://globaltranslation.com/demo/global_translation/beta/userfiles/files/wejilenozuwogajez.pdfIn PDF document text
    • https://www.hs-hofgastein.salzburg.at/ckfinder/userfiles/files/disobefekonigu.pdfIn PDF document text
    • http://cimkezes.hu/uploads/ckfinder/userfiles/files/gulatobitidufililesamabaj.pdfIn PDF document text
    • http://dent-pro.cz/pic/file/pabusuraworunud.pdfIn PDF document text
    • https://xn--nmqu14inmf.com/upload/files/15650464676.pdfIn PDF document text
    • https://redac.ch/upload/fekosixibivis.pdfIn PDF document text
    • https://hsse.hssanesteban.cl/files/gefimidetuguwokuwaresig.pdfIn PDF document text
    • http://staractivecollection.com/resimler/site/files/degab.pdfIn PDF document text
    • http://salman-is.com/userfiles/file/jufuma.pdfIn PDF document text
    • http://benthanhsgfarm.net/images/uploads/files/56924786054.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=quick+craft+minecraft+pePDF 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_off0000ba30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA30 10556 bytes
SHA-256: 0da7bc5099998a015f425dd18173af32d904b4a767ecd6388ac4170513fb9db8
font_01_sfnt_off0000d258.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD258 16584 bytes
SHA-256: a7ba7b8f50aed3459c5224861390b84f235e4c0452b0528a13065629cc4928df
font_02_sfnt_off0000fd0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD0C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1