Malicious PDF — malware analysis report

Static analysis result for SHA-256 2542eb8b7034de3f…

MALICIOUS

PDF

80.3 KB Created: 2021-09-12 17:20:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c07289e8323b7064dfa291b91b239f73 SHA-1: 636b6efc86628beb3e3e1f4d43aa8b9953b5d914 SHA-256: 2542eb8b7034de3f3d481d2d0919dcf77f7709791bbef56ca8008ea0644ce16f
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple compromised or disposable domains, likely for phishing or malware distribution. The presence of numerous PDF links on potentially compromised WordPress uploads and disposable hosting further supports this malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://artiguardia.pl/userfiles/file/89489737604.pdf
    • https://renewone.de/files/kumoredukekitut.pdf
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/251f59c99bf2d86a926a3bd1ad60470a/rojuw.pdf
    • https://www.hotelamoha.it/wp-content/plugins/formcraft/file-upload/server/content/files/161379a624899e---wesotom.pdf
    • http://ajisushionline.com/uploads/files/sobosuzoxino.pdf
    • https://perfecthospitals.com/ckfinder/userfiles/files/27864320305.pdf
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/sesf6bmth8mh910q9am3mm3fjv/gubiwagi.pdf
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/e5g28dif587mrgvv1iv0s9mv07/92394170037.pdf
    • http://easytravel63.ru/ckfinder/userfiles/files/wabuxijawatelosituralig.pdf
    • http://rsentco.com/upload/file/73114154631.pdf
    • http://kursverwaltung.fit-n-essen.ch/ckfinder/userfiles/files/dinukiliwereropipajifog.pdf
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/hjdpris98jt0sc1c5tc0ug7lin/62819875127.pdf
    • https://ihappywash.com/uploads/files/202109100818318127.pdf
    • http://ahkkpcm.org/userfiles/20083808603.pdf
    • http://sun-green.nl/ckfinder/userfiles/files/19214649912.pdf
    • https://www.mnogotrop.com/ckfinder/userfiles/files/67575612743.pdf
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/1d57cc8289ea877bf3181fc97ac29ddd/folubigijipigo.pdf
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/42a3370b47213c7b8ba1f65b58fbf88f/xurovawud.pdf
    • http://nakamurasangyou.jp/app/webroot/uploads/files/45239811176.pdf
    • http://demo755.webbazaar.com/uploads/giwunetusokikag.pdf
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/161300076d2288---jorub.pdf
    • https://duragloss.pl/userfiles/file/memijosulopadikugejemob.pdf
    • http://www.lnk-creation.fr/upload/file/29766829488.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=change+currency+in+play+store
    • 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_off0000d5be.bin
b1ead1d3a0458fbb80ca67857902effa1acec423648fbf86edcf1f3642e9a970
pdf-font-stream PDF embedded font (sfnt) at offset 0xD5BE 10900 bytes
font_01_sfnt_off0000eef2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEF2 16792 bytes
font_02_sfnt_off00010704.bin
c12c4dea0af3b7c07a665ab1b43f6c45b7d10541a3256635184e35b1b9fcf4a0
pdf-font-stream PDF embedded font (sfnt) at offset 0x10704 17376 bytes