Malicious PDF — malware analysis report

Static analysis result for SHA-256 2c16cd76f7880bf1…

MALICIOUS

PDF

96.7 KB Created: 2021-06-27 20:01:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d7807e67521a2dbd9703a5192c0ed4a6 SHA-1: b11e4c2a7dacd488bfc8ccacb94cbcd21e88e071 SHA-256: 2c16cd76f7880bf1666854c07def703937d462acde92558b6e85b332d81fea4e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains embedded JavaScript and a large number of external URIs, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users. The primary purpose appears to be to lure victims through a phishing attachment and then redirect them to malicious content hosted on compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

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://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/160738bea546d9---11383068571.pdf
    • http://yfatc.com/userfiles/file/3382653215.pdf
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a6fb4902b89---18722166460.pdf
    • http://gat-asset.com/CKEdit/upload/files/valobamebowivek.pdf
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b977d6c074---59378241798.pdf
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6436f5868d---10063131493.pdf
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/f6067e3cfef6303bfc87d699d593d9a3/68859871319.pdf
    • https://www.baileysmilk.com/wp-content/plugins/super-forms/uploads/php/files/9fc37c5e9b39af677846fc94c5e4ddba/sujeduterejifafufik.pdf
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c37d7c5f375---nalogu.pdf
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609e82e8b8552---73545624260.pdf
    • http://littlepearlbooks.in/data/eimages/file/54059701530.pdf
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/5ab4bc444cb7b4e286bfbb58bf514ae7/vadanenexerijadomasol.pdf
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088fd929f4a5---73497437416.pdf
    • https://parklanehotel.asia/userfiles/file/vuvudaripebi.pdf
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a550b752c16---tikagiro.pdf
    • http://www.maderas-navarro.com/ckfinder/userfiles/files/20890929305.pdf
    • https://canvasations.com/wp-content/plugins/super-forms/uploads/php/files/u2jl2s7ouqcv6lqddsdbmc1cp3/18271499142.pdf
    • https://gagiongvitgiong.com/ckfinder/userfiles/files/xotowufunoweg.pdf
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/99lfcc9mil8k5o0tib2fboqd23/dotir.pdf
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1607daaf76353b---41257872993.pdf
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1606f316d902f3---kivawiritipebigog.pdf
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/fe16c41996d3f632e67805aaa5c71c2c/86037419501.pdf
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160c2f6abcbd43---wujutikowotaxot.pdf
    • http://zs-g.jp/app/webroot/js/ckfinder/userfiles/files/saziwupatoxexonozudulis.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=darcy%27s+letter+to+elizabeth
    • 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_off00011b47.bin
0c7fdd35523289037f36adb830b0fb95ccf6c975cc82180dc9e6d5fc02a1257f
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B47 16160 bytes
font_01_sfnt_off000144d6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x144D6 16792 bytes
font_02_sfnt_off00015ced.bin
cc0469e6a0d81930558b9fde78745021b5ef6383d58873812a18cbabe9e07ca5
pdf-font-stream PDF embedded font (sfnt) at offset 0x15CED 10572 bytes