Malicious PDF — malware analysis report

Static analysis result for SHA-256 0bc33bcd5374bd3f…

MALICIOUS

PDF

85.2 KB Created: 2021-07-27 20:22:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ccac931092bc7e2f334b0f8d3ab1bdfd SHA-1: be4e1b3a2349569671775ffa8a02919b752421d3 SHA-256: 0bc33bcd5374bd3f940580b6f68a0cba8a168209c808d03ab3bc5098accfb640
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to compromised or disposable domains. The document body is heavily obfuscated and unreadable, suggesting it's not intended for direct user interaction but rather to host these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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 http://tandprotheses.com/ckfinder/userfiles/files/69210402043.pdf
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/40e160f796fdf46a8cd7833499ef9043/48150180283.pdf
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c1634c2e42---ruzakuxaxitipopepakedusi.pdf
    • http://hillcountryawningsandsunscreens.com/wp-content/plugins/formcraft/file-upload/server/content/files/160755b8a05462---dipata.pdf
    • http://brcassociati.com/userfiles/files/jorarogevunajat.pdf
    • http://esipro.fr/userfiles/file/zoxilun.pdf
    • https://photojet.net/userfiles/file/pipizikefemer.pdf
    • https://aspaeng.com/files/image/files/milexoloriwekapubazos.pdf
    • http://savannahcentury.info/clients/4/44/449a5b3489ef279447e90cf6cdd72f1c/File/nagumikiribusilava.pdf
    • http://stananddiane.com/clients/6/67/672a2699e369d648dd23e03de9deda78/File/nodedukojiwuxitizofaperi.pdf
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/4557d13b7dcb2f76158c8c81a870a9b5/tajaso.pdf
    • http://www.tractortools.cz/ckfinder/userfiles/files/javixu.pdf
    • https://www.vignolaweb.it/ckfinder/userfiles/files/bavaralemi.pdf
    • http://thegioituigiay.net/uploads/files/96605614711.pdf
    • https://cortemadera.com/wysiwygfiles/file/66251181406.pdf
    • https://chamsocmuihong.com/wp-content/plugins/super-forms/uploads/php/files/58bv3i7mlpdnv7tt469butj3v1/60976732467.pdf
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca078c0ba5---vugedami.pdf
    • http://france-ex.com/images/blog//file/zanagafezositekowuter.pdf
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b4ab565d0af---38604643662.pdf
    • http://myafmc.com/clients/a/a5/a51d49d85de18111a3d718c63a5e5081/File/kidakaxeravenizuvidubisu.pdf
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f1f5e1748be---52038109390.pdf
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160c5e279e4097---sisifenozexudoro.pdf
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160782daccfd84---13516111729.pdf
    • http://konemara.hu/userfiles/file/6770044917.pdf
    • http://pronobile.de/catalog/file/wetisifovudozenodewi.pdf
    • http://davidhammerstein.org/userfiles/file/sumorobizobisojojuwubizit.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=fill+in+the+blanks+with+suitable+words+worksheet+for+grade+1
    • 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_off0000e984.bin
056a2a08f7829cc83c9f6c75d2a91f094ebd0d24c096a6bea36cf4c035f8dfbc
pdf-font-stream PDF embedded font (sfnt) at offset 0xE984 16560 bytes
font_01_sfnt_off00011439.bin
d84190815633162c1017d4cdbcd306d846c0fdf94243220c38e8efe36838ed73
pdf-font-stream PDF embedded font (sfnt) at offset 0x11439 11080 bytes
font_02_sfnt_off00012dd5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12DD5 16792 bytes