Malicious PDF — malware analysis report

Static analysis result for SHA-256 7cf971140d0fb7f0…

MALICIOUS

PDF

104.8 KB Created: 2021-07-02 20:11:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 259fa367cbc17c6b57a041996003552f SHA-1: 5c25f692781169b94909d8fef58cb73b6fc3e8cb SHA-256: 7cf971140d0fb7f073d00c6e207111b7be9de127f5e4d4c15ab5958b0bdfceca
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, which is a common technique for exploiting PDF vulnerabilities or initiating malicious actions. It also features a link farm pointing to numerous disposable domains and compromised WordPress sites, suggesting an attempt to obscure the final destination and evade detection. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9926

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=posttest+in+a+sentence
    • https://newchat.xyz/js/ckfinder/userfiles/files/79736264839.pdf
    • https://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/bc02277aad7ad007ffe6a719be9ba8bb/nafananoruruzedabexufafex.pdf
    • http://www.abcklima.hu//data/editorfile/sodixafit.pdf
    • https://dixietemporarystorage.com/wp-content/plugins/super-forms/uploads/php/files/7832bafe0c28a8f34bc66f17bbbd8760/revibisutanetiwexu.pdf
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16082bdabe1ecc---serativebimopa.pdf
    • https://www.hediyevideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606eb1cda7e26---28586106426.pdf
    • http://meta-min.com/files/17624206696.pdf
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/7e88503b608d85f0bf8e702f671c6575/pesemig.pdf
    • https://bilbox.es/wp-content/plugins/super-forms/uploads/php/files/780d4563068abd97968ff08950afbbf6/20006983715.pdf
    • https://gionggiacam.com/ckfinder/userfiles/files/13125243243.pdf
    • https://djennebeads.com/nbloom/fckuploads/file/vokizelevu.pdf
    • http://houstontca.org/Content/uploads/files/77630706185.pdf
    • http://sad-azov.ru/wp-content/plugins/super-forms/uploads/php/files/c4bd97de9b5c14450c0e49bfa5b1ab2a/lotizelutiwaxivafabigiv.pdf
    • https://ises.ca/phpsites/vertical_living/uploads/file/46026740810.pdf
    • http://www.bufolari.com/public/immagini/file/jufukoritovudowudag.pdf
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/eatgoqnt5iu5s254vuo57r29j0/58445067064.pdf
    • http://nickels.design/ckfinder/userfiles/files/bedenodumogozuxuji.pdf
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a2a29d988a4---kilijirim.pdf
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/oaocnc8u28r2nskrjffun0i96k/83817755517.pdf
    • http://aahsclassof1978.com/clients/b/b6/b6117739535924054831d33ecd54b00a/File/45506787544.pdf
    • http://anatolianlgs.com/userfiles/file/dalawoduxisesibiterojula.pdf
    • http://coyada.com/up_images/up_images/nobasulepetafikokekadu.pdf
    • http://bluekeydigital.com/images/pic/file/67529096462.pdf
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/8fh7bkcsdunf8lmgn2451tae74/82148284040.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_off000135a4.bin
4a97bb311504fd76fc2ec2c50450d8da859ccedbe5517752e61f4a5bafcb6972
pdf-font-stream PDF embedded font (sfnt) at offset 0x135A4 18660 bytes
font_01_sfnt_off0001660a.bin
de9c9f0bb7ae0d689d8c174fb5dcb9b8652f7242c8431fff96bc92e750a4995b
pdf-font-stream PDF embedded font (sfnt) at offset 0x1660A 10076 bytes
font_02_sfnt_off00017cab.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x17CAB 16792 bytes