Malicious PDF — malware analysis report

Static analysis result for SHA-256 b66b50513ee532a7…

MALICIOUS

PDF

83.0 KB Created: 2021-09-07 08:56:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 0aaf37301a399297a74e4178c70033ab SHA-1: 1ec7c326bbb18dae55837efe76d4359a0bc65e9a SHA-256: b66b50513ee532a7b0ce1dc424e4530603bc53cf8029429ec5ef5d61d9d68c53
156 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, and the document body was unreadable, so the rationale is based on the URL heuristics and AV detections.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://coretry.ru/uplcv?utm_term=schwing+stetter+concrete+pump+sp+1400+manual PDF link annotation
    • https://samowar.ch/upload/file/wotulodotimavupili.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/0e035cd876b5a1b500b5205cee0daded/35162562389.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e17f86c1c84---25260146776.pdfIn PDF document text
    • https://12tiga.com/contents//files/49282357100.pdfIn PDF document text
    • http://officinedesign.it/userfiles/files/jekataroze.pdfIn PDF document text
    • https://sitycare.com/FCK-UserFiles/files/95627300148.pdfIn PDF document text
    • https://atlantidegattico.it/file/50473414581.pdfIn PDF document text
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/8b579a1f5736fcb098ca020c695beac4/subujosi.pdfIn PDF document text
    • http://huh.hu/UserFiles/File/luwev.pdfIn PDF document text
    • http://cabinet-blin.fr/ressource/site-image/files/kogudadu.pdfIn PDF document text
    • http://sahamit.net/userfiles/file/vumunanife.pdfIn PDF document text
    • http://cdwy028.com/uploadfile/file/20210525051513.pdfIn PDF document text
    • http://medica-eg.com/userfiles/file/46241158716.pdfIn PDF document text
    • http://vankouwenenmastop.nl/UserFiles/file/pekeviralonumife.pdfIn PDF document text
    • http://greaterdeliveranceministries1.com/clients/61527/File/nomawudodedopofiwujugari.pdfIn PDF document text
    • https://askisan.com/upload/ckfinder/files/kodogefeke.pdfIn PDF document text
    • http://allaboutdowney.com/userimages/duwavibekobimunofiwer.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b0cebf32f9---zaradisepenafalo.pdfIn PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/ckb9ek7hhsu7e1l2g46m68j0o5/14509133314.pdfIn PDF document text
    • http://stalmost.pl/userfiles/file/42685819846.pdfIn PDF document text
    • http://lumieretvie.com/userfiles/file/fivekusapanibumewomorer.pdfIn PDF document text
    • https://stpeterscbs.ca/ckfinder/userfiles/files/subara.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000de92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE92 17332 bytes
SHA-256: f85cdec1ddd95776a4de486e279a0e8cd600a119797117525a8791e423f6d1d1
font_01_sfnt_off00010b96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B96 11336 bytes
SHA-256: f913d1cce8f0732b47381a25c458ca5ab76e8f10759056bdfd65f4c4b1ce8a34
font_02_sfnt_off00012636.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12636 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1