Malicious PDF — malware analysis report

Static analysis result for SHA-256 44f157609b9ee1d2…

MALICIOUS

PDF

84.6 KB Created: 2021-08-25 12:08:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 11d17c16bb96b5dbb2fd2132a51e855e SHA-1: af4950e1ef34fb39fde99f391499bcdb2f5992e3 SHA-256: 44f157609b9ee1d2d4601dbe11c01afe1bffbde8dd0a5dcb2e9a4959cd4e2c26
176 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to distribute malicious files. ClamAV detection and ML classification confirm the malicious nature of the PDF, likely serving as a lure for users to download further malware. The presence of multiple PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://ambvetbrashersclavoghisu.eu/userfiles/files/dexarelamisigexedileri.pdf In PDF document text
    • http://windowsplusllc.com/ckfinder/userfiles/files/pipesevafevuju.pdfIn PDF document text
    • https://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/a4669474362a3117aeb01a84d0960966/pixute.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/4ju8shhett3ffbej974e6ishq1/93417590302.pdfIn PDF document text
    • http://khunghinhdepphuctin.com/media/ftp/file/28363597718.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c58d0537a2---8196130458.pdfIn PDF document text
    • http://gruppocaminiti.it/userfiles/files/rufaxofaxuvu.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be5ea5b8196---78714264986.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/9fe687f354b9bdbf4e3adf85fd555d8a/28906007599.pdfIn PDF document text
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf04d66d15a---tusamugewapapa.pdfIn PDF document text
    • https://salvatoredivilio.it/userfiles/file/63826856621.pdfIn PDF document text
    • https://2-view.org/home/view/public_html/ckfinder/userfiles/files/54478511121.pdfIn PDF document text
    • http://104.156.58.56/~web2inbox/wp-content/plugins/formcraft/file-upload/server/content/files/16088cdb275685---zenufijijijesawojepulu.pdfPDF link annotation
    • http://holyfamilycyo.org/clients/37654/File/31868121518.pdfIn PDF document text
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/ldh7q038d60farjf0fn26dsm48/97908900349.pdfIn PDF document text
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078f497aa888---gujewujojelujed.pdfIn PDF document text
    • http://jjw-led.com/userfiles/file/64968992006.pdfIn PDF document text
    • https://locoffice.ru/userfiles/file/73268249276.pdfIn PDF document text
    • http://clingac.es/d/files/5513287593.pdfIn PDF document text
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160847ed1c7268---vumulasuxivi.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/bawosexe.pdfIn PDF document text
    • http://donghocasiochinhhang.net/uploads/userfiles/file/siduvirudekekiwuw.pdfIn PDF document text
    • http://aiskreunion.com/clients/b/b4/b417c2091670ce0b0d78f4b231aea02c/File/petuluwinefobozefejimuti.pdfIn PDF document text
    • http://myshopgroup.com/userfiles/files/votowe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=two+color+seed+stitchPDF link annotation
    • 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_off0000e47a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE47A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fc8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC8C 17752 bytes
SHA-256: ce8279e7066a274f55cd4e3753bdd0a45fdd8a124a19b9d808ba6186af106825
font_02_sfnt_off00012b4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B4E 10252 bytes
SHA-256: 7f824dedb148162a24c0d2ca46f2ff6c46c6380f101923ef491b6f2a504e34cd