Malicious PDF — malware analysis report

Static analysis result for SHA-256 b40b9135227c808d…

MALICIOUS

PDF

89.6 KB Created: 2020-12-28 08:38:18 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: e8c0bbab723ffb5b059188d1c98491ab SHA-1: 559797a61ff3e46b9cc236fac511f31d90451d0c SHA-256: b40b9135227c808d39e106baf7110d7599a4706db9faca45add76fd9520b2419
252 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links pointing to external PDFs hosted on disposable domains, a technique often used for SEO manipulation or to distribute malware. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of a redirector link further supports the malicious nature of this document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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
  • 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://ggtraff.ru/aws?utm_term=consolidated+balance+sheet+example+excel In PDF document text
    • https://sobemifukoku.weebly.com/uploads/1/3/4/8/134887972/4251433.pdfIn PDF document text
    • https://nirejabepifu.weebly.com/uploads/1/3/4/2/134266024/dokisujirifur.pdfIn PDF document text
    • https://lomimasexoguxi.weebly.com/uploads/1/3/4/7/134736135/bcbe195c7375fa.pdfIn PDF document text
    • https://temazojirilezin.weebly.com/uploads/1/3/2/3/132302863/592fdfa7d4d789a.pdfIn PDF document text
    • https://cdn.sqhk.co/xuwisagilevi/Ehikrft/2495967630.pdfIn PDF document text
    • https://mepafuxutare.weebly.com/uploads/1/3/4/6/134660934/gosifigodasawi-dizowuxu-dazorodeviv-bulapivuzuwile.pdfIn PDF document text
    • https://cdn.sqhk.co/bolomekurufe/bghShdd/dilefakadavibewodor.pdfIn PDF document text
    • https://lotagixowila.weebly.com/uploads/1/3/1/1/131164100/fexizidumod.pdfIn PDF document text
    • https://deguverafutaw.weebly.com/uploads/1/3/4/5/134501054/gazubev.pdfIn PDF document text
    • https://woperuxotuxolo.weebly.com/uploads/1/3/4/8/134849923/456379.pdfIn PDF document text
    • https://xigujevaw.weebly.com/uploads/1/3/4/7/134701692/58623.pdfIn PDF document text
    • https://koxulisel.weebly.com/uploads/1/3/4/6/134600043/kirurababu-zifevefafupeji.pdfIn PDF document text
    • https://tabogivazosepa.weebly.com/uploads/1/3/1/8/131871767/xojemipejosog.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.opentle.orgIn PDF document text
    • https://uploads.strikinglycdn.com/files/a0dbf559-cab2-4d5d-9574-3b66e1e59759/melerepuje.pdfIn 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://scripts.sil.org/OFLIn PDF document text
    • http://www.gnu.org/licenses/gpl.htmlIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ec4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC4D 5328 bytes
SHA-256: ab03400eca683d4ab78cbe385a573c5d40c6570c5657a548bd65677ce9c0c960
font_01_sfnt_off0000fe37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE37 11744 bytes
SHA-256: 38f612185936ddf5be20b06c515e4e218c3fd3aa62687c902c1a3d3002526870
font_02_sfnt_off00011e5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E5D 10664 bytes
SHA-256: 15fc69cbb82634aa1879084c0b16acb589943b3b1b167026ff8a753060c04f57
font_03_sfnt_off000142f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x142F5 16204 bytes
SHA-256: a95eff378c135b1ab40d10b3cd1da1bafbc07f86005f57898d079c90d712ddbd