Malicious PDF — malware analysis report

Static analysis result for SHA-256 dcab9ab97ab550f8…

MALICIOUS

PDF

75.4 KB Created: 2021-03-28 01:45:45 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-07
MD5: a2ad6a41cb75dd40ea9dc62e528e9de8 SHA-1: 0536a106da4f0f41f52927cd1d9bcb8e6213efd3 SHA-256: dcab9ab97ab550f81552eb07ee478a05eef5873928fadfc429ccfd871fef4072
194 Risk Score

Malware Insights

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

The PDF contains a large number of external links, indicating it is part of a link farm designed to manipulate search engine results or host malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and numerous external URLs are indicative of a malicious document, potentially leveraging embedded JavaScript for further actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://zajinet.ru/wix?keyword=sample+collection+letter+for+medical+officer PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4387428/normal_5fdeab73a1a1b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367645/normal_600da7cd35216.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4481825/normal_5ff116c2dfd98.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4385848/normal_5ff4318530410.pdfIn PDF document text
    • https://cdn.sqhk.co/koxopumo/bjeqPgw/58338350370.pdfIn PDF document text
    • http://vovpomnim.ru/i_sing_the_body_electric_song_wikidbw3t.pdfIn PDF document text
    • https://cdn.sqhk.co/sokulutesi/jfheidj/1781195577.pdfIn PDF document text
    • https://cdn.sqhk.co/lilovenodi/dNibebX/xutebinob.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451561/normal_5fd5f17b7b4c6.pdfIn PDF document text
    • http://magicwoolshop.com/pipe_roughness_tableiaajg.pdfIn PDF document text
    • http://prostotit.site/sezususorolejohobwq.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4471467/normal_60522a0471407.pdfIn PDF document text
    • https://cdn.sqhk.co/xozifejor/gjec1ha/55012779183.pdfIn PDF document text
    • http://nosinoski.shop/sofewumezagadelipijugs08g.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4501486/normal_604ad26abd698.pdfIn PDF document text
    • https://cdn.sqhk.co/nelufebo/BhdgHhe/46678036150.pdfIn PDF document text
    • http://fruitslope.online/visekiforusizitkacl.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://e53c8fcc-339b-4d8f-83f6-44ddc8c6ace4.filesusr.com/ugd/1ea9c4_18e025fdb8fe4e258ebc4ac03a662552.pdf?index=trueIn PDF document text
    • https://0ca3454e-05ac-49fc-8d00-644b1af7be3c.filesusr.com/ugd/8bf3fc_35de0b55d7104d1a892418796a732e23.pdf?index=trueIn PDF document text
    • https://88e92b2d-3ddf-41b2-a2ae-4af48bfba274.filesusr.com/ugd/b74686_8e5f09553b5c469d8725716764d144f2.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e9b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9B6 5228 bytes
SHA-256: 126da4ce542ab41e9e96e35309e52b53ae3724eca06d0e596a44efc37cb63483
font_01_sfnt_off0000fb68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB68 10720 bytes
SHA-256: 9256bf60b70e2385fff0e0e9f4299d40df26125a78d3ce48716ee1ef7462f783