Malicious PDF — malware analysis report

Static analysis result for SHA-256 82eb1c7d11350d35…

MALICIOUS

PDF

84.7 KB Created: 2021-07-16 19:52:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 76c3f418cc1124de6c6bce058b6f110a SHA-1: 31bc3f8e5cea6729a991fef47b155b87d22fe01f SHA-256: 82eb1c7d11350d353f81e01eb99b4696ed834f1b723203cc305ed0d0e3c5b00d
156 Risk Score

Malware Insights

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

The sample was identified as malicious by a ML classifier and ClamAV, specifically as a phishing trojan. It contains numerous links pointing to compromised WordPress upload storage and other disposable hosting, suggesting a link farm designed to redirect users. The PDF's structure and embedded links indicate it's likely used in a phishing campaign, possibly as a lure to download further malicious content or steal credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa2556cab5f---44515763709.pdf
    • https://t2sc.me/userfiles/65572915779.pdf
    • http://davidhammerstein.org/userfiles/file/18422627979.pdf
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/ef77833ed33f42bdfba3dd2477d4345e/kiwusaf.pdf
    • http://ankaser.com/userfiles/file/88494384358.pdf
    • https://proektasis.gr/admin/spaw2/uploads/files/giluwuta.pdf
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099318d93b5c---xapomogemevuvikupufem.pdf
    • http://buffagiuseppeinfissi.com/userfiles/files/95477435557.pdf
    • https://nolimitscenter.be/peausitive/images/FCKeditor/file/36104020516.pdf
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/vipuv.pdf
    • https://demircanticaret.com/userfiles/file/29975581865.pdf
    • https://homini.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16089a3937a915---57779962236.pdf
    • http://ufnk.fr/app/webroot/files/file/rudajesela.pdf
    • https://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/b0d1d3ef91a966a6b94bbabf2f69e82a/3762133584.pdf
    • http://xn--80aafkqcanfpgnhbng3b5i9a.xn--p1ai/pict/file/51132210669.pdf
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/289bfb9bcf9c8c5cf543067297959d63/nixikixobidopubo.pdf
    • http://skrabl.pl/www/rpbd/fck/file/mobozubamifozilaloxupe.pdf
    • http://agataklimowska.pl/userfiles/file/jimodufu.pdf
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/1609ec9b5aacbe---mogivawunogexabukaxuxeme.pdf
    • https://seataclighting.com/wp-content/plugins/super-forms/uploads/php/files/9c525b2720071c3cb33c39cfd819d41e/3387447174.pdf
    • https://tedvandergulik.nl/userimages/file/maxusewadidogunoroka.pdf
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/13j2ati7053dncd9ggej0jndul/jejim.pdf
    • http://www.communityheroesproject.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b4a34404f67---febiwegemidimibagaguseno.pdf
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609fa1757d575---60032678097.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=how+to+remove+permanent+retainer
    • 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_off0000e9bf.bin
658daa11b0a07e3505a9b3cb022a7d1969bc9e0d61467bac5db2c26d373253d5
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9BF 17124 bytes
font_01_sfnt_off00011651.bin
34c59dd12a09581214850144ec3e10efcd11da8bf42d5dae229c48e167d116d4
pdf-font-stream PDF embedded font (sfnt) at offset 0x11651 10344 bytes
font_02_sfnt_off00012da3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12DA3 16792 bytes