Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3a67c0e78409de4…

MALICIOUS

PDF

88.6 KB Created: 2021-07-17 18:57:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 14f96b985afc85021dc01aac2cf1f057 SHA-1: c2db97b3b01ea894f35ea24ce02e64210bba3c63 SHA-256: a3a67c0e78409de4583c12aaf7cdd5458a030467a5b1c6b0f39263ef79004ebb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm with numerous URLs pointing to compromised CMS upload directories, a common technique for hosting malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of multiple links on disposable hosting and the use of UTM parameters suggest an attempt to obscure the true destination and potentially engage in SEO poisoning.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608c39f74d660---xebeberibapevu.pdf
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608bfdc6e7754---50986878351.pdf
    • http://bong-dem-long.org/upload/editor/files/15490495719.pdf
    • https://anthonygillant.com/userfiles/file/nodekojisuf.pdf
    • http://bosch-service-center.ru/uploads/files/zapavanosowajuwivesusade.pdf
    • http://stromzeleny.cz/file/61437792812.pdf
    • http://springswellness.net/wp-content/plugins/formcraft/file-upload/server/content/files/16098932dbfe7b---papemozuwotol.pdf
    • http://ownlines.com/upfiles/file/70354444988.pdf
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607acc8d7fd7b---zibivuzisil.pdf
    • http://premsaktidal.in/userfiles/file/jejeke.pdf
    • https://chamsocmuihong.com/wp-content/plugins/super-forms/uploads/php/files/rarchlbteaneimuunuao3vr1g6/62431451071.pdf
    • http://medica-eg.com/userfiles/file/37725174235.pdf
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1606d127255c99---86661869635.pdf
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/160997a64852ad---dakudikamekusunosinemized.pdf
    • http://basaritarim.net/admin/editor_resim/file/wofifesaxenadu.pdf
    • http://synowka.pl/galeria/file/65314705411.pdf
    • https://businessservicesuk.com/userfiles/file/xezoxe.pdf
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/n02oc8lbmmhao8i6oq8dgsqhg1/mizobaf.pdf
    • https://lightspec.com/wp-content/plugins/super-forms/uploads/php/files/ea394a29b1bcc665d1ac2fb8a3595e92/65053859154.pdf
    • http://sun-eko.eu/files/file/bixufenemeku.pdf
    • http://projectbudapest.hu/wp-content/plugins/formcraft/file-upload/server/content/files/16074fb0c5cf31---37703308873.pdf
    • https://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/qljj9amuv0cidhh9u6qa5ii1uv/21233555625.pdf
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/l4n1m5mruf7ehdb5fvdsrku0ru/jolonanimana.pdf
    • http://allaboutdowney.com/userimages/18802541182.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=translate+english+from+indonesia
    • 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_off0000f70e.bin
eb38526ef28b0399f605ff9a7ad240a5008aa67173888d28f7b05d65a2f71348
pdf-font-stream PDF embedded font (sfnt) at offset 0xF70E 17872 bytes
font_01_sfnt_off000124b5.bin
73f5da26091509bb495c1a25dd8be24ed8c4f1b86b459568e7816ecc2f672c8d
pdf-font-stream PDF embedded font (sfnt) at offset 0x124B5 10764 bytes
font_02_sfnt_off00013d0d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13D0D 16792 bytes