Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3e5bfcd35eb89c3…

MALICIOUS

PDF

80.7 KB Created: 2021-03-20 06:50:00 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 67ffa6c9dc11602d12d4e95f93c3af10 SHA-1: bd53cbd9e9c149a476ace04c41d50e0db73f526e SHA-256: b3e5bfcd35eb89c3f5c196095284f5b7356e796357a501468835dc3259abb7e8
194 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document functions as a link farm, presenting a deceptive search result for a dictionary to entice users to click on external links. The PDF_SEO_LINK_FARM heuristic indicates a large number of external links, many hosted on disposable domains, suggesting a malicious intent to redirect users to potentially harmful content. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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 https://kuzutuzo.ru/award?keyword=oxford+english+arabic+dictionary+pdf+free+download PDF link annotation
    • https://fuxarudoniw.weebly.com/uploads/1/3/5/3/135350341/6d31d37b0e54.pdfIn PDF document text
    • http://sizegoduxuxa.mygamesonline.org/34079803264.pdfIn PDF document text
    • http://wotukujis.sportsontheweb.net/vavasubug.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375507/normal_60317f1b91e0d.pdfIn PDF document text
    • https://cdn.sqhk.co/satidaruxami/gcGjgb6/faxinelexaxasotunug.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413968/normal_602db2d12a021.pdfIn PDF document text
    • https://cdn.sqhk.co/dogatefi/ujjsSbO/89318585187.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4407747/normal_5ff7c1110c52e.pdfIn PDF document text
    • http://lizoguxumugef.mywebcommunity.org/82561834996.pdfIn PDF document text
    • https://zezogilak.weebly.com/uploads/1/3/0/8/130874046/bapadibinatuxofuli.pdfIn PDF document text
    • http://serawuv.mygamesonline.org/45013979647.pdfIn PDF document text
    • http://birebap.scienceontheweb.net/keto_diet_food_list.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://59bb578d-b312-442a-858b-1a1a54b18a6c.filesusr.com/ugd/c79b1c_5bc2435e353f4d6daebe21ed7b73e023.pdf?index=trueIn PDF document text
    • https://ff19a39e-637c-4fc6-80cc-750024e8dd37.filesusr.com/ugd/d217e2_45310a79ab3f473d9ec4b1231d9cb70c.pdf?index=trueIn PDF document text
    • https://c1f973cf-d719-4acb-8f9e-cd83ae4fb94d.filesusr.com/ugd/057766_dac018aec4bc4ae0a46b9b4aed8083e1.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/zowejunef/julozeji.pdfIn PDF document text
    • https://s3.amazonaws.com/zuwosil/where_was_the_revenant_filmed_in_alberta.pdfIn PDF document text
    • https://b585a76b-fab5-4024-b0d2-f3ad95444197.filesusr.com/ugd/404203_3e8b31fbb00b4dde9dc7fbfa2d2f8d34.pdf?index=trueIn PDF document text
    • https://4cf6c2b4-cd84-4b73-83b1-bf7f441162b2.filesusr.com/ugd/e50c99_8cca009c9afb41e186ee30f44916a9c2.pdf?index=trueIn PDF document text
    • 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
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off00011778.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x11778 18012 bytes
SHA-256: a3213e5c23863c9a8c862c91da95f5e1566bcadf60edcf371e1a69d2997a350e
font_00_sfnt_off0000de32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE32 5848 bytes
SHA-256: 6715f8d803bc1831a600f0a61e3f69a819ace26a1429c03023eb91fd8bf2a1a0
font_01_sfnt_off0000f22b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF22B 11032 bytes
SHA-256: 129f8a991ac2b2bb93715ee891687b87c8848d9ed0a46a3cca63c8d3996de568