Malicious PDF — malware analysis report

Static analysis result for SHA-256 ce9b16c9dcee6cfd…

MALICIOUS

PDF

67.4 KB Created: 2021-09-28 00:26:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a279d7fb2e5b587bae10c2b5a576ec86 SHA-1: b2ca452949949cefb718f797cc843e593e0eea85 SHA-256: ce9b16c9dcee6cfd65830ef0af771e27f26b0f0bc6cf1087824860097fec1109
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded URLs that point to various domains, many of which are associated with compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, further obscuring its true intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://qiangka.com/ckfinder/userfiles/files/sukewozasebajilewoz.pdf In PDF document text
    • https://tdfstore.it/file/lukewatub.pdfIn PDF document text
    • http://zhhyhb.com/uploadfiles/files/87026272388.pdfIn PDF document text
    • http://foto-recepty.sk/images/fotky/65419423648.pdfIn PDF document text
    • http://salamatekhanevadeh.ir/ckeditor/files/files/towizowogexi.pdfIn PDF document text
    • https://gadd-asso.org/userfiles/file/wefoduzufidolulisixem.pdfIn PDF document text
    • https://demoliman-host168-com.twbiz.me/data/html_editor/files/88277081306.pdfIn PDF document text
    • https://hotararicedo.ro/files/files/30196496796.pdfIn PDF document text
    • https://xn--80aaijz0c.xn--p1ai/ckfinder/userfiles/files/6730745585.pdfIn PDF document text
    • http://www.supair-lux.hu/ckfinder/userfiles/files/77385936455.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/66f026cb536072a42c06fab165b5dbfe/wemijufufiruma.pdfIn PDF document text
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134d531df59a---35767682752.pdfIn PDF document text
    • http://magendans.com/imagefiles/file/wosasazigejokufepevovo.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b99d1dbd7b---gejiwejipupige.pdfIn PDF document text
    • http://www.adarshvidhyasankul.org/userfilesfile/movumowowejimibozip.pdfIn PDF document text
    • http://autosvilar.com/uploads/ckfinder/files/bupatoxizazotaluzujununi.pdfIn PDF document text
    • http://moestuinwebshop.nl/userfiles/file/72886795632.pdfIn PDF document text
    • http://groupementpecheduloir.com/ckfinder/userfiles/files/bugilivovaxuxolorup.pdfIn PDF document text
    • https://reitinguok.lt/userfiles/file/nozujafidupenaw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=stick+n+find+app+androidPDF 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_off0000aa07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAA07 10436 bytes
SHA-256: 7f26b74ad91fff4b8285031048e145d7aab48409a8a3f4b5578082f23cf380c4
font_01_sfnt_off0000c1d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1D1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000d9e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9E3 15068 bytes
SHA-256: ba6c322b9afa0273f0852c6ecf1243e8543a0c39effa51b500787a39258ca121