Malicious PDF — malware analysis report

Static analysis result for SHA-256 0c9059c7b41c9295…

MALICIOUS

PDF

80.9 KB Created: 2021-09-17 07:08:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 7b6ff231dba8ba35904408a00c58683e SHA-1: c0e5036962551d327917c792a5667b5c3e655c5e SHA-256: 0c9059c7b41c9295fc1bd2ba8d950155a7d1bc62be7aeaa0d67d02cc4cf09020
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded URLs, with a significant heuristic identifying it as a link farm on disposable hosting, suggesting an attempt to redirect users to malicious sites. The document body is heavily obfuscated and unreadable, but the presence of external URIs and the link farm heuristic strongly suggest the intent is to lure users to external, potentially malicious, content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://philabc.ru/uplcv?utm_term=which+browser+is+best+for+downloading+in+android PDF link annotation
    • http://sadiqandsons.com/userfiles/files/56886222544.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/tutusegimuxi.pdfIn PDF document text
    • http://thementalhealthadvocates.org/files/userfiles/file/nonuzedadanodexikonelurin.pdfIn PDF document text
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613a1881ae5e6---64925270857.pdfIn PDF document text
    • https://hotelindigha.com/FCKeditor/file/87177336844.pdfIn PDF document text
    • https://vishalahospitality.com/ckfinder/userfiles/files/pulibud.pdfIn PDF document text
    • http://benthanhsgfarm.net/images/uploads/files/86187904359.pdfIn PDF document text
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/99c7ab3ffe815d031d38440330129466/45220404902.pdfIn PDF document text
    • http://happinessgown.com/upload/users/files/77445697775.pdfIn PDF document text
    • https://www.hotelrestaurantmacarena.fr/ckfinder/userfiles/files/80353027033.pdfIn PDF document text
    • http://friulanamarmi.it/images/file/pikeza.pdfIn PDF document text
    • http://viral-list-machine.com/ckfinder/userfiles/publics/files/21076778565.pdfIn PDF document text
    • https://bnbcostaverde.it/userfiles/file/fukaxupema.pdfIn PDF document text
    • https://maintogelonline.info/contents/files/40266867772.pdfIn PDF document text
    • https://cahayamimpi1.com/contents/files/ralugevata.pdfIn PDF document text
    • https://pottoka.info/files/galeria/files/1119243144.pdfIn PDF document text
    • http://whipitleather.com/userfiles/file/77909563827.pdfIn PDF document text
    • https://spitalmoldovanoua.ro/ckfinder/userfiles/files/tonujeweke.pdfIn PDF document text
    • https://eastmangroup.org/ckfinder/userfiles/files/japele.pdfIn PDF document text
    • http://ketoanantamhcm.com/uploads/files/widurop.pdfIn PDF document text
    • http://forumts.com/ckfinder/userfiles/files/kulenegajogewavikurizolu.pdfIn PDF document text
    • http://alwaysshine.com/fileimage/file/41047895135.pdfIn PDF document text
    • https://bulgariapools.com/contents/files/pumabofikivazuwobarujis.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_off0000d97a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD97A 16784 bytes
SHA-256: cbf0e8cb21d0a2bb2a0713f5040ac33dc2f62cbda548187fc1ce9fd2492e623a
font_01_sfnt_off000104b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104B1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011cc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CC8 10972 bytes
SHA-256: 4fbc04112113e18f1692693f7b44df0db56eba072643c9bc2186e694ecac35bd