Malicious PDF — malware analysis report

Static analysis result for SHA-256 da43b7fb7e73a984…

MALICIOUS

PDF

76.8 KB Created: 2021-09-11 19:11:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: fa6e5dac6671b7db5f371714e2e345d1 SHA-1: 045a264a43874c98bccca59a2b5e658d941a23b2 SHA-256: da43b7fb7e73a984632db3319e0c2f50be500452a2ec36e68a54537880db61be
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm, with multiple URLs pointing to disposable hosting and compromised CMS upload storage. The presence of numerous external URIs suggests an attempt to redirect users to malicious sites for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://queure.ru/uplcv?utm_term=firestick+tv+apk PDF link annotation
    • http://dynamic1984.com/user_file/file/89459656332.pdfIn PDF document text
    • http://szjg.hu/images/file/44370024647.pdfIn PDF document text
    • http://s2ipower.com/survey/userfiles/files/77105980754.pdfIn PDF document text
    • http://derkwoo.com/upload/editor/files/dabagadovadawuvepofadu.pdfIn PDF document text
    • https://onlinendttraining.net/files/xutobewize.pdfIn PDF document text
    • https://sunwayhk.com/louis/STARKGROUP/ckfinder/userfiles/files/lipegorozotow.pdfIn PDF document text
    • https://31app.com/userfiles/file/87754019253.pdfIn PDF document text
    • http://rsport.eu/yonexshop/static/file/liralimu.pdfIn PDF document text
    • http://pjteam.hu/uploads/sipikuvivoxefi.pdfIn PDF document text
    • http://seattleteriyaki3.com/uploads/files/dinuvud.pdfIn PDF document text
    • http://yarpb.ru/pic/userfile/forunekemon.pdfIn PDF document text
    • https://grupo-kayros.com/userfiles/file/tumafugejimikasebizirug.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/161355836ac864---77327497488.pdfIn PDF document text
    • https://avistravel.ro/userfiles/file/34384296645.pdfIn PDF document text
    • https://totalsewa.com/userfiles/file/mubovanaz.pdfIn PDF document text
    • http://cwesp.biz/upload/file/jovisagodugera.pdfIn PDF document text
    • http://enjoyisagenix.com/ckfinder/userfiles/files/99417922339.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613b7e4581eca---93887460733.pdfIn PDF document text
    • http://contentworks.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161336e23575f6---37798494736.pdfIn PDF document text
    • https://primer-spb.ru/files/files/99294703094.pdfIn PDF document text
    • https://wickedcheesy.com/images/file/57811100490.pdfIn PDF document text
    • http://kuryakyn.ru/userfiles/file/44523719293.pdfIn PDF document text
    • http://beergolfers.com/blog/images/file/50276082778.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_off0000c942.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC942 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e159.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE159 10232 bytes
SHA-256: 4d319f8f649a6352125ae7728ca5d72f039e3879080e4f40bff91932965a63be
font_02_sfnt_off0000f887.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF887 17620 bytes
SHA-256: a2030548972c9f70a61bb10b2e7092259959863052b1526fa595f7ee6c4ac997