Malicious PDF — malware analysis report

Static analysis result for SHA-256 5143f7c7d78a1028…

MALICIOUS

PDF

69.7 KB Created: 2021-09-14 05:45:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: d275fc529bcb2f4b0efdeda053918f78 SHA-1: a00465f68cce8e95a46493ea5da0a87da49545c9 SHA-256: 5143f7c7d78a1028691764c6e83a0715effd32696ff9630e81634f0906d7347d
162 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which are hosted on compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution via these links. The embedded JavaScript is likely used to facilitate the redirection or obfuscate the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7455

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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=pdf+logo+remover PDF link annotation
    • https://cissud.eu/uploads/ck_editor/files/94924401824.pdfIn PDF document text
    • http://konikanarrowfab.com/ckfinder/userfiles/files/38455789398.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132f6d796c3a---83181825994.pdfIn PDF document text
    • https://journeypeople.cc/wp-content/plugins/super-forms/uploads/php/files/7de5c854c2163efd25dcb0e56a726993/zivofererekuninelugutufow.pdfIn PDF document text
    • https://heritran.vn/uploads/news_file/munivo.pdfIn PDF document text
    • https://www.ebenisterie-burette.com/ckfinder/userfiles/files/gebaxebaz.pdfIn PDF document text
    • https://anhhuynoithat.com/asset/files/85552112626.pdfIn PDF document text
    • https://eghamatkade.com/basefile/eghamatkadecom/files/gikufo.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613db2572dffe---terilisivuxenejidukujoj.pdfIn PDF document text
    • https://jnnjhansi.com/userfiles/file/64665839102.pdfIn PDF document text
    • https://aprenda-atdi.com/uploads/files/22463557584.pdfIn PDF document text
    • http://manilag.com/FileData/ckfinder/files/20210913_E52FC386FDF1C2CF.pdfIn PDF document text
    • http://sanraimundo.cl/dyn/uploads/file/16198548130.pdfIn PDF document text
    • https://nyig.com/files/file/89303192637.pdfIn PDF document text
    • http://skisun.it/userfiles/files/fafegadupalanugasijepe.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/ca6bd89f7b0912ee1b8ec392087e21a9/73031564512.pdfIn PDF document text
    • http://mastera-mix.ru/ckfinder/userfiles/files/nopulatexeso.pdfIn PDF document text
    • http://2990592.ru/ckfinder/userfiles/files/50368772269.pdfIn PDF document text
    • http://www.iuoelocal870.com/kaizen/ckfinder/userfiles/files/58280744217.pdfIn PDF document text
    • https://dobre-akce.cz/media/files/file/24340634753.pdfIn PDF document text
    • http://artio.pl/files/files/16383011969.pdfIn PDF document text
    • http://colegiosantarosa.com/uploads/imagem/file/sijisizuluvorobej.pdfIn PDF document text
    • http://vektor28.ru/userfiles/file/63395427553.pdfIn PDF document text
    • http://recepti.plovdivweek.com/js/ckfinder/userfiles/files/kodekomavukosogaxefu.pdfIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d728.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD728 10140 bytes
SHA-256: 147a8d42cc0fc9dd404c77202d1f05392603217600ba8fc3d7357ff7b705fd5a
font_01_sfnt_off0000ed9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED9F 18292 bytes
SHA-256: adc3d3185e109e5634eb1636d80879acbc75e8e50ff932b876a288625248644c