Malicious PDF — malware analysis report

Static analysis result for SHA-256 18492f2e9f2bbe43…

MALICIOUS

PDF

78.1 KB Created: 2021-08-29 10:06:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 63a13101da82dacd1f65b52ebf9aeb98 SHA-1: 1ba4d5471cd138ac058ba5ebe08544a0c0010b4a SHA-256: 18492f2e9f2bbe43868a2a22a33cfc651cd078fed41fb94f422157e79561c2f5
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://indecomavo.pl/inc/zumexilutafitag.pdf In PDF document text
    • https://almuhja.com/ckfinder/userfiles/files/97922229654.pdfIn PDF document text
    • http://metabolit.ru/files/file/gobevaxa.pdfIn PDF document text
    • http://studiomedicoveterinariobellucci.eu/userfiles/files/95092897766.pdfIn PDF document text
    • http://studiosiciliani.eu/userfiles/files/12252403369.pdfIn PDF document text
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/pdaqpte5vpp6jal2946bbstujg/78291488391.pdfIn PDF document text
    • http://smartvoicecom.com/userfiles/lejozavepolatawowudutusu.pdfIn PDF document text
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/29f8cc212dc7ddf39b9c0e440739e6ac/bexemefajunokokesijomol.pdfIn PDF document text
    • http://ashioke.com/images/library/File/xafesegutubitofa.pdfIn PDF document text
    • https://bostoncake888.com/UserFiles/files/zavesudadukipujalut.pdfIn PDF document text
    • http://ypdtools.com/ckfinder/images_store/files/dubutadubedanebej.pdfIn PDF document text
    • http://stroi-sistema.ru/img/fovelisi.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160840f8e72e30---sogajejalekuvigor.pdfIn PDF document text
    • https://radiosmile.hu/upload/file/seloxo.pdfIn PDF document text
    • http://archi1919.com/smlclub-files/file/5141192393.pdfIn PDF document text
    • http://clubselectionvoyages.com/images/file/naxebotovojowaliwavag.pdfIn PDF document text
    • https://ksboutlet.com/file/files/fazimukizabuxovibazuzok.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/160917d4329011---62995139854.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a364f471733---84222471105.pdfIn PDF document text
    • http://chaukitchen.com/uploads/files/78441051366.pdfIn PDF document text
    • https://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/94db9a791968978774d2ea8957cf5919/nofupu.pdfIn PDF document text
    • https://www.comperat-89.fr/ckfinder/userfiles/files/pudamimigadelusopix.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/2d989acf10d3ed3578b29c54c10ce930/82516233265.pdfIn PDF document text
    • https://www.eoluk.com/wp-content/plugins/super-forms/uploads/php/files/pr9ib0cjipmcel2rbm4lnuk0m0/rerodagufolenolefadagaj.pdfIn PDF document text
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/059vdo30g5n6il20kmi6bjnu6j/46397297194.pdfIn PDF document text
    • http://akinmedikal.com/uploads/file/fojutijolujubik.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=questions+on+living+and+non+living+thingsPDF 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_off0000ca02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA02 10652 bytes
SHA-256: 4d02547736991df702603b961006c91906d137e191319a7fc0919a4622a72f16
font_01_sfnt_off0000e243.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE243 18804 bytes
SHA-256: 719bc8bb58fc587ce53e29fa127601cd1952c391ba5bbfe79c031472ab4657fa
font_02_sfnt_off00011275.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11275 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1