Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c62c0c4a9bf8f57…

MALICIOUS

PDF

76.8 KB Created: 2021-09-13 23:52:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: a1977f94e690b848dbb00fbe274c14fc SHA-1: 6bac120d9426d69ba1c864514f11a3c7b3b72293 SHA-256: 4c62c0c4a9bf8f576ebd76d4845e25720704056783cf8b4c45e6803c4f76ea8b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to external sites, including those hosted on compromised CMS upload storage. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware distribution sites. The presence of multiple external links suggests a link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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
  • 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 https://paardenwelzijnscheck.nl/app/webroot/files/ckeditor_files/files/34211285353.pdf In PDF document text
    • http://campfirewtx.org/userfiles/file/18347331619.pdfIn PDF document text
    • http://xn--interpeas-r6a.es/upload/files/guzesotitawanosupuxuve.pdfIn PDF document text
    • http://retrofotr.cz/files/file/27211651281.pdfIn PDF document text
    • http://nzozkrowodrza.pl/uploads/editor/file/35633287018.pdfIn PDF document text
    • https://taiwancy.com/app/webroot/userfiles/files/6424844670.pdfIn PDF document text
    • http://studioagronomoserragiotto.eu/userfiles/files/1734915649.pdfIn PDF document text
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16138601c1e476---xelotaxolulaje.pdfIn PDF document text
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/16139d1a15cb9d---buvojivawomovabilerabepur.pdfIn PDF document text
    • https://movimientofamiliadejesus.com/images/uploaded/file/nuzadisakezazowawisava.pdfIn PDF document text
    • https://www.peltonfell.org.uk/ckfinder/userfiles/files/vulisutipuxovitafe.pdfIn PDF document text
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/2099989971442965cc3fd97cfa381824/45776847775.pdfIn PDF document text
    • http://portableandcool.com/files/files/7494470613.pdfIn PDF document text
    • http://etasystem.net/userfiles/files/56367104363.pdfIn PDF document text
    • https://408of53crownstreet.com/assets/media/files/80031506111.pdfIn PDF document text
    • https://ciiinnovationsummit.com/ci/userfiles/files/bagup.pdfIn PDF document text
    • http://sdhmladavozice.cz/userfiles/file/lubisova.pdfIn PDF document text
    • http://madiagranitosilano.it/userfiles/files/wutunigoxulugoladeke.pdfIn PDF document text
    • http://www.s-prom.si/fileupload/file/xirofipukupafutofafezena.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ea5f433d94---munafesubirezaxenudenujo.pdfIn PDF document text
    • https://arerp.kr/data/file///76683975191.pdfIn PDF document text
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/60a942c30a3b47c30967df05a2eb141d/23670890564.pdfIn PDF document text
    • https://tdfstore.it/file/fonifuzelomi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=little+foxes+michael+morpurgo+pdfPDF 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_off0000c551.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC551 17928 bytes
SHA-256: e331680ca4dd45765cfe1be3b30758deb2267705d95edca5573b0d85ef895375
font_01_sfnt_off0000f3b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3B4 11124 bytes
SHA-256: 2f6c970f485e123d1f72a2d3d081eb67f3a8c345ca1667999d6bb93e1d536e49
font_02_sfnt_off00010d79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D79 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1