Malicious PDF — malware analysis report

Static analysis result for SHA-256 41bd22566e3799cf…

MALICIOUS

PDF

100.0 KB Created: 2021-07-04 21:42:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: eebb121daf23581d2446633b0dd4b9da SHA-1: 661816e6d749cace3d948974a84a25d9f929409e SHA-256: 41bd22566e3799cf0b97e846b9c8f8cf674dd3d9c0cc83fc9d01b7f35776ad4c
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites and disposable domains, indicating it functions as a link farm. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware. The document body was unreadable, but the heuristic firings clearly indicate a malicious link distribution pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9928

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://hutbephottaihaiphong24h.com/upload/files/68373767782.pdf
    • http://kxnjl.com/userfiles/files/11923168492.pdf
    • https://www.alphaveneers.com/wp-content/plugins/super-forms/uploads/php/files/5849b00081047cef8d68487e43c2d909/86534936176.pdf
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae8c71c02dd---bavudavafeken.pdf
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/t9ldo94fa9k88dt0dl12du15o6/wagatonozizo.pdf
    • https://people11people.com/uploads/File/91397007904.pdf
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/16096ce457077f---74145564148.pdf
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c70d55a0332---2876154776.pdf
    • http://baudoinfamily.com/clients/f/fc/fc66627f90e8a365851b026dcf169025/File/taduwurizomukegel.pdf
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a67ac143e85---gipogivonodokixaseno.pdf
    • http://hocikto.info/userfiles/file/10683214456.pdf
    • https://ferado.vn/userfiles/file/gosowotipuzatigizapexo.pdf
    • https://nepalimodelagency.com/userfiles/file/kutugezamav.pdf
    • https://ddc-touggourt.dz/ar/files/72656749989.pdf
    • http://se-ty.ru/uploads/userfiles/file/gutesatab.pdf
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609e47cca218e---wokewogajavukofus.pdf
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/2oo67f9us4cs1nr50m7smdatc4/paxusutip.pdf
    • https://west-holding.com/userfiles/file/74356481826.pdf
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb5a7706ec6---tigezilupimoxeruzazapud.pdf
    • https://eseninternational.com/uploads/files/43883218573.pdf
    • http://gezond-trakteren.nl/kasteel-doornenburg-img/bestandenfile/midovotibowasudir.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/qj93tnch09ddoftu0uog0dkodc/95865325762.pdf
    • http://dijladentalcenter-qa.com/userfiles/file/bofonenutanekijul.pdf
    • https://www.baileysmilk.com/wp-content/plugins/super-forms/uploads/php/files/a5819da2ab0577bf6c1a1f360073b61d/favalolakusosa.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=first+pick+in+fantasy+football
    • 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_off0001239f.bin
e6f4e59b808e6e10e1798be09acfebe343bc93b6648a6706f511fcde8d64d5bc
pdf-font-stream PDF embedded font (sfnt) at offset 0x1239F 10664 bytes
font_01_sfnt_off00013bf6.bin
dcbf7773eb503ac3773be8899cb1e40bff1d0d4aaefad9cca5152ae4c5dea686
pdf-font-stream PDF embedded font (sfnt) at offset 0x13BF6 17284 bytes
font_02_sfnt_off0001691f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1691F 16792 bytes