Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef2fdb6c37ced7c4…

MALICIOUS

PDF

76.1 KB Created: 2021-06-25 15:55:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 17c8850b99fd20731782a26526065daa SHA-1: e62a961576d6585708a1c66a9855f8fa0511791f SHA-256: ef2fdb6c37ced7c426fa71f01c43a71a4870408bdd928dda6953235e72df711c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which are part of a link farm hosted on compromised or disposable domains. These links likely serve as redirects to phishing pages or malware download sites. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://smidgel.ru/uplcv?utm_term=square+root+of+variance
    • https://watertorens.nl/userfiles/file/sapepuroj.pdf
    • https://advance-pack.com/editor_upload/file/65817900546.pdf
    • http://asja-doll.ru/userfiles/file/96744050359.pdf
    • http://www.phsdcenter.com/temp/js/ckfinder/userfiles/files/pulaxox.pdf
    • https://www.nrlandscapes.co.uk/wp-content/plugins/super-forms/uploads/php/files/70534da0978a089006685455f902d958/fafomuvenawulejakat.pdf
    • https://adepotcustom.com/UploadFiles/file/20210503143358143.pdf
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a32809608c3---ruvimaninebubuxegin.pdf
    • http://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/u3om9vjcud7fsh0c9640fo0jbe/lodavi.pdf
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609c71d6d71fd---31562482879.pdf
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160949642357e1---80545949223.pdf
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072db6a910d9---dotowelawanotefizid.pdf
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5aa37ae9b3---75583852895.pdf
    • https://www.harasportcenter.com/wp-content/plugins/super-forms/uploads/php/files/gbfutbr72ik1ntnm4glhb5ghib/dipemoxu.pdf
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/655vqmlg84kre9lhb393djifu6/zinovetegurove.pdf
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/0463244ab4983ed6633be9296779cb50/pamonezemapatuwajexa.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c976.bin
f8b78abafcee04f5fab536b8527b90bdc4503ba70cf1b0b8910384531443cc01		 pdf-font-stream PDF embedded font (sfnt) at offset 0xC976 10500 bytes
font_01_sfnt_off0000e189.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1		 pdf-font-stream PDF embedded font (sfnt) at offset 0xE189 16792 bytes
font_02_sfnt_off0000f99b.bin
bf472f4a428495dd657a3f066efae89a2989930cac50f7fc90c2fe3876901dc8		 pdf-font-stream PDF embedded font (sfnt) at offset 0xF99B 16308 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.