Malicious PDF — malware analysis report

Static analysis result for SHA-256 78a5ee46d81ca90f…

MALICIOUS

PDF

81.0 KB Created: 2021-09-13 01:32:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ea285d3e0486760d38d0e1472d9a0b90 SHA-1: d1cb63b94e8be2e23ef21395c2cc291b7cb8f120 SHA-256: 78a5ee46d81ca90f96ca8285d499436ffa72962095281d1ac2bc6f1d194615f7
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to unknown PDF files hosted on various domains, several of which are identified as potentially compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://rubella2.integra-sh.com/userfiles/file/zawilasuwexedixe.pdf
    • https://sjamsul-hidajat.id/ck_uploads/uploads/files/rapedakov.pdf
    • https://thietbivesinhanhhuy.com/asset/files/48139643873.pdf
    • http://naso10.com/userData/board/file/sizewuvemufof.pdf
    • https://rowanmkt.com/Uploads/ckfinder/userfiles/files/79990338973.pdf
    • http://fskyok.com/uploadfile/files/duxatejapiwene.pdf
    • http://philipwillettelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/32348377639.pdf
    • http://letdentalab.com/img/files/38724042785.pdf
    • http://ck-buhgalter.ru/userfiles/file/rekem.pdf
    • https://xuanhongkhang.com/upload/files/37418681355.pdf
    • http://tko.wavedev.net/img/files/files/galunekiri.pdf
    • http://files.ibiza-ferien.de/file/polakujepog.pdf
    • http://kemenyseprosiklos.hu/upload/file/60661102005.pdf
    • http://studiotecnicodavico.eu/userfiles/files/65419387375.pdf
    • http://putzlappenborner.at/editor_up/52645157070.pdf
    • http://sadiqandsons.com/userfiles/files/mitoliribu.pdf
    • http://esistore.com/userfiles/file/tojoworaxejaxowudijigod.pdf
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/161346db0e50bc---41512027564.pdf
    • http://1day2night.com/UserFiles/file/fibemum.pdf
    • https://quasar.mago.ro/ckfinder/userfiles/files/41009085542.pdf
    • http://ttccid.com/userfiles/file/49026747949.pdf
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c110259ec7---40152529392.pdf
    • https://ijmscr.com/ckfinder/userfiles/files/nomiforobilomawakoradax.pdf
    • https://www.info-service.com.tw/plugin/ckeditor/ckfinder/userfiles/files/5950630108.pdf
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/1612ebc8b22704---dewugenazemavetufutuser.pdf
    • https://zifu-tech.com/app/webroot/userfiles/files/55669149156.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=how+to+remove+text+notification+on+android
    • 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_off0000d49d.bin
725690c836a39ec5e543e1c4dd1e6358dcef68e933ce68890b1fe68019d2921a
pdf-font-stream PDF embedded font (sfnt) at offset 0xD49D 19004 bytes
font_01_sfnt_off00010556.bin
11127a9f5a631b6c0c714fb8529e783610ef61e3c554252fce297e5e22c1ad45
pdf-font-stream PDF embedded font (sfnt) at offset 0x10556 10668 bytes
font_02_sfnt_off00011dcc.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11DCC 16792 bytes