Malicious PDF — malware analysis report

Static analysis result for SHA-256 a0213bd4e249e740…

MALICIOUS

PDF

87.0 KB Created: 2021-07-08 12:00:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a7a3c9564233dbcf6028bcfe842341a5 SHA-1: e842828852616fb91de3740fcb73d41f2b36d42f SHA-256: a0213bd4e249e740a2fcb3abb423c5f4ce0a7210c125cd02fb1fca9041d5744c
96 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, many of which point to compromised CMS upload directories. The ML classifier strongly indicated maliciousness, and the link farm structure suggests an attempt to redirect users to potentially malicious content or phishing sites. No scripts were extracted, and the document body was unreadable, limiting further analysis of the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 5

  • 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://keifo.ru/ckfinder/userfiles/files/vopob.pdf
    • http://nirmalapublicschoolerumely.com/userfiles/file/nunogev.pdf
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/sq93u3clvaqrglj9re8k6fkcmb/sarajukaza.pdf
    • https://bistakalikotenetwork.com/userfiles/file/24231691634.pdf
    • http://drironcat.com/images/file/55110122533.pdf
    • http://navigator-nsk.ru/userfiles/file/fokipijenapobe.pdf
    • https://rclurie.com/wp-content/plugins/super-forms/uploads/php/files/b2fd11ad372c83e610b8e8db15e1f96b/88906664191.pdf
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074d482a0970---78161854855.pdf
    • http://gagutp.com/sa_upload/userfiles/file/20210602020613.pdf
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608736c565080---56853773497.pdf
    • http://geyikkimya.com/userfiles/upload/file/84829687773.pdf
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079d5ca148bc---15358674918.pdf
    • https://quaint-house.com/karovobewexadavorijokulu.pdf
    • https://hondamienbac.vn/userfiles/file/97254826423.pdf
    • http://asokmontridental.com/userfiles/file/sozalixaruwunumudijid.pdf
    • https://cal.lighting/wp-content/plugins/super-forms/uploads/php/files/8f3f06d93c71ba24a02d76a33b1c8331/30248660470.pdf
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/160946a85f024a---wikometipibeb.pdf
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/qibddrbv28kuhejp5ji7nvt656/xinasutigigepolobogud.pdf
    • https://www.fangjin.org/ckfinder/userfiles/files/86532724043.pdf
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160908e9aca663---nuvoxewu.pdf
    • http://archgeo-leszno.pl/uploads/userfiles/files/73586392565.pdf
    • http://www.franklinwebdesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099efe0c7c84---terizotavoxafefuka.pdf
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/2fq9sqch713amkpiclv9rgl6s0/vemotobozamujopu.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=19+lincoln+ave+scituate+ma
    • 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_off0000f0f8.bin
01f4fd0d4b3856f90e44bbff9ec60ad94fc298058a0a8c167eac345956d3379a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0F8 17484 bytes
font_01_sfnt_off00011e80.bin
75f6d0b4ee453af42a627f6da1e136a8970a02a3d05b98298669430d2115c2f3
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E80 10580 bytes
font_02_sfnt_off000136c3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x136C3 16792 bytes