Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ccff82de65b5319…

MALICIOUS

PDF

79.8 KB Created: 2021-09-10 00:44:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 139e8819c5df72f992a12b8af975317c SHA-1: 7a2498da08adeda19b24a3d9944e9b95cbd235b7 SHA-256: 8ccff82de65b5319ef5b1993b04670f0c2cfc1c7f634a1088fd382e305e5b478
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Static analysis revealed it functions as a link farm, containing numerous URLs pointing to various domains, some of which are hosted on compromised CMS upload directories or appear to be disposable. These links are likely intended to lead users to phishing sites or download further malicious content.

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://tourister.kr/userfiles/file/96806390249.pdf In PDF document text
    • https://www.fishhabitatnetwork.com.au/application/third_party/ckfinder/userfiles/files/gumafezom.pdfIn PDF document text
    • https://alixdemassy.fr/userfiles/file/mufedifubefisiwijekor.pdfIn PDF document text
    • http://kurskodkb.ru/page_edit/_samples/userfiles/files/jonix.pdfIn PDF document text
    • https://rentcar888.com/uploads/files/202109070759599191.pdfIn PDF document text
    • http://back2wood.de/userfiles/file/fepatawalo.pdfIn PDF document text
    • https://buildingexpertsdirectory.com/ckfinder/userfiles/files/funotokudolegabefawod.pdfIn PDF document text
    • http://zae.me/datafiles/file/firodesixabulizesuxeguwo.pdfIn PDF document text
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1612fbd3f0f896---mowixoxakuk.pdfIn PDF document text
    • http://sculecuacumulator.ro/app/webroot/files/userfiles/files/dafaputugote.pdfIn PDF document text
    • https://footballsod.com/images/ck-uploads/files/79312278704.pdfIn PDF document text
    • http://elektromig.pl/userfiles/file/50588824329.pdfIn PDF document text
    • https://southernwashpros.com/nbloom/fckuploads/file/padaroxinu.pdfIn PDF document text
    • http://netmutum.com/userfiles/file/93801385928.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/hpf3pbnv5dfp9mrj65n2id5foc/voranokebixerogaxewi.pdfIn PDF document text
    • http://movesearchesuk.com/userfiles/file/tagif.pdfIn PDF document text
    • https://martabaktelor.com/contents/files/wimukebif.pdfIn PDF document text
    • http://zhouzhuank.com/v15/Upload/file/2021911918267712.pdfIn PDF document text
    • https://kisikana.hr/UserFiles/files/pesujalanoxozenatix.pdfIn PDF document text
    • http://www.motocams.cz/ckfinder/userfiles/files/98672566428.pdfIn PDF document text
    • https://equinox-e.com/upload/files/kozab.pdfIn PDF document text
    • https://cokhivietuc.com/img-vietuc/files/48769786049.pdfIn PDF document text
    • http://aesg2edcv.handylover.com/upload/files/fumawenebigeniz.pdfIn PDF document text
    • http://kossuthdigisuli.hu/userfiles/file/38359855521.pdfIn PDF document text
    • http://dbexpertise.fr/catalogue_dynamique/file/62222398442.pdfIn PDF document text
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/9edbdd5254c9552f2038552127fc2f03/96217097255.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=android+kunjappan+ver+5.25PDF 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_off0000d3f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3F8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC0A 17228 bytes
SHA-256: f02cc60a96c335043d44deb51f3cc3f03de1735241793da460c639a33bebe8fc
font_02_sfnt_off00011855.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11855 10764 bytes
SHA-256: d91efd60256a1a4cba5e97355c57f9fbb3d9d10435b74690ebde253bc8498447