Malicious PDF — malware analysis report

Static analysis result for SHA-256 a233f50c00d83d60…

MALICIOUS

PDF

83.6 KB Created: 2021-01-09 22:47:18 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 65f8914ac86755637a2822504a9b23a9 SHA-1: 21bfe6ea443bd091ec119eafc21423bb5303f086 SHA-256: a233f50c00d83d606bd0494aa7f3728b46d5d353197b6d4dff943badd9eeb664
252 Risk Score

Malware Insights

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

The sample is identified as a malicious PDF by multiple heuristics and a machine learning classifier, specifically flagged for containing malicious redirector links and acting as a link farm. The embedded URLs, such as 'https://gettraff.ru/aws?utm_term=comprehensive+chemistry+practical+class+12+pdf', are indicative of phishing or malware distribution campaigns. The presence of numerous links to disposable hosting services further supports its role as a malicious redirector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://gettraff.ru/aws?utm_term=comprehensive+chemistry+practical+class+12+pdf In PDF document text
    • https://tabogivazosepa.weebly.com/uploads/1/3/1/8/131871767/7390570.pdfIn PDF document text
    • https://cdn.sqhk.co/savimatuv/h7pZRii/zikajapom.pdfIn PDF document text
    • https://cdn.sqhk.co/todusukiraxi/iahdehl/gomupawoguxazene.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4529087/normal_5fd5f4674d87c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374682/normal_5fdbc329da49e.pdfIn PDF document text
    • https://winomumamo.weebly.com/uploads/1/3/1/0/131070375/7987181.pdfIn PDF document text
    • https://cdn.sqhk.co/sezelijimofi/quRgh3s/9692587076.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413462/normal_5fbe8912359ae.pdfIn PDF document text
    • https://widalafamibag.weebly.com/uploads/1/3/0/8/130814492/nelowuretim.pdfIn PDF document text
    • https://cdn.sqhk.co/tiwumixe/S1Nu0eF/6890151543.pdfIn PDF document text
    • https://kuxozofaxaxasij.weebly.com/uploads/1/3/5/3/135325708/sevires.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4389603/normal_5ff71684736da.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/jevuxozazebazug/pejepuze.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://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_off0000d7bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7BC 5644 bytes
SHA-256: 5ddbca6adcda1d73c1ae15ed98a2102e4ce0a879dd1826a03e12c7ca5f3b47c1
font_01_sfnt_off0000eac9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAC9 7536 bytes
SHA-256: 18ce016d7c06f5ac46f1ed2c225a7a82f9825d776c2f92779c3394dd2d972fb7
font_02_sfnt_off0001002b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1002B 11388 bytes
SHA-256: e9ff9aeba5dd3410c885111009e007ef6eb7f9395c20fde51fa75d58c5c07fdf
font_03_sfnt_off00012728.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12728 17492 bytes
SHA-256: e6236245b1b519c90993a0a0decb83651aa70bd3eb3f1615240c4a875e4479e0