Malicious PDF — malware analysis report

Static analysis result for SHA-256 99a8657d195aee3e…

MALICIOUS

PDF

79.9 KB Created: 2021-03-16 18:19:08 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 35b6acbfe23fdc85918a1ccc58792e4d SHA-1: b86a7fbb3d8fb0dd0403abfabe3ca000fc0562f6 SHA-256: 99a8657d195aee3e03aae0d9f344181e6139bfbb5ca469c4d8301546ac75cc66
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, with one heuristic specifically identifying a 'PDF link farm' containing 30 external PDF links. The primary external URL, 'https://botokaw.ru/wix?keyword=hairstyle+guide+city+folk', suggests a lure to a potentially malicious site. ClamAV detection and ML classification strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://botokaw.ru/wix?keyword=hairstyle+guide+city+folk
    • https://static.s123-cdn-static.com/uploads/4426820/normal_5ff87d61b569c.pdf
    • https://cdn-cms.f-static.net/uploads/4414691/normal_5fd17f327f721.pdf
    • https://cdn-cms.f-static.net/uploads/4369163/normal_5fe99da552b63.pdf
    • https://cdn-cms.f-static.net/uploads/4375521/normal_602faa67e5dd3.pdf
    • https://cdn-cms.f-static.net/uploads/4369936/normal_6027458a9354e.pdf
    • https://minedikatew.weebly.com/uploads/1/3/0/7/130739540/jobobeko-xivukeg.pdf
    • https://ditugapagijesap.weebly.com/uploads/1/3/4/6/134651304/jilararipenot-lurow.pdf
    • https://lexilovomab.weebly.com/uploads/1/3/1/4/131452944/warok.pdf
    • https://cdn-cms.f-static.net/uploads/4469836/normal_60201b63d38cc.pdf
    • https://static.s123-cdn-static.com/uploads/4455881/normal_5ffc66756fe15.pdf
    • https://wovupidej.weebly.com/uploads/1/3/4/6/134687137/pabewukukep.pdf
    • https://cdn-cms.f-static.net/uploads/4478383/normal_600a4fa9355ab.pdf
    • https://cdn-cms.f-static.net/uploads/4375702/normal_600a049a964af.pdf
    • https://static.s123-cdn-static.com/uploads/4481509/normal_5ffb9643bdba8.pdf
    • https://cdn-cms.f-static.net/uploads/4444370/normal_60474a3daa822.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/julaxel/paxujapudadanukowekugenug.pdf
    • https://s3.amazonaws.com/murudute/sapavoketiwex.pdf
    • https://s3.amazonaws.com/nelizenejakarug/autocad_2010_free_online.pdf
    • https://s3.amazonaws.com/lupebesu/49056391546.pdf
    • https://uploads.strikinglycdn.com/files/9fd904fa-b71c-4100-9fc3-4b42225c33f1/hp_deskjet_3050a_printer_price.pdf
    • https://s3.amazonaws.com/xunilukegez/busizonameraxudugilo.pdf
    • https://uploads.strikinglycdn.com/files/ca2c6889-2833-4ba8-8b39-d59c0c273677/what_is_a_synonym_for_catch_sight_of.pdf
    • https://uploads.strikinglycdn.com/files/36aa2e59-ae35-4490-a840-8748d0fd0eb9/5939286707.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fc46.bin
a8f6ec27631a8bc62cb9a3d6a085099c65dfa67c3491563d55bf46d69c43223e
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC46 5316 bytes
font_01_sfnt_off00010e76.bin
157a090812a693a68b2c97e2e9a4c134f8fbc83d64e983393add82b89e6db817
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E76 10524 bytes