Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b705afd555c1436…

MALICIOUS

PDF

71.9 KB Created: 2021-09-16 06:27:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c889da6a24cae1362766b31aadbcf270 SHA-1: 4874843769e8a575bf2a90f48300fa97e3c0ccaf SHA-256: 8b705afd555c14367cfa1a0586f65f3664d859fc974ab08eb2456204f61da158
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the document functions as a link farm, presenting numerous URLs hosted on compromised CMS uploads and disposable domains, likely to trick users into downloading further malicious content. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM firings supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • 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 link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • 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 http://35ju.21tg.cn/uploadfile/ckeditor/files/bibijikuxukozitozav.pdf
    • https://goldenparadisestsimons.com/wp-content/plugins/super-forms/uploads/php/files/26785beec340eb1d606c43d32b0462f7/rosimafi.pdf
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130174bdbf86---38616845369.pdf
    • http://bretagne.annuaire-regional.com/ckfinder/userfiles/files/11577677296.pdf
    • http://wdnederland.nl/file/57829372033.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140eb16598b0---rovozojupemusovakuzubup.pdf
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e86f5e2d4d---52793204398.pdf
    • http://lexxyin.net/files/fckeditor/file/burerutokezopatufujuk.pdf
    • http://taigesw.com/upload/files/65154881433.pdf
    • http://avision-italia.com/userfiles/files/xukupe.pdf
    • https://podiummagazinenews.com/ckfinder/userfiles/files/gifirone.pdf
    • http://hrudolf.com/userfiles/kizololexufoliba.pdf
    • https://functionalmovement.gr/wp-content/plugins/super-forms/uploads/php/files/4653f1948b1d9ee47740e16786c6fb32/zokujiju.pdf
    • http://gardenofsound.com/userfiles/files/natinuzideriw.pdf
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/1612f368030539---sazidorilotagovixikow.pdf
    • https://martan.es/cenavarra_userfiles/files/82928403948.pdf
    • http://chayka-svg.ru/files/90719245838.pdf
    • https://thefertilizergranulators.com/d/files/91506870304.pdf
    • http://budaors.varosom.hu/userfiles/files/928699632.pdf
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/161359eac2a795---76499645853.pdf
    • https://pbanerjeeservices.4digitmagic.com/userfiles/file/bibafipo.pdf
    • https://mimpiindahsatu.com/contents/files/juxazovizodoginexaguse.pdf
    • https://aaaxxion.info/images/file/39169113567.pdf
    • http://cctsw.net/whly/up_files/FCK/file/20210905_005210_123.pdf
    • http://vzwsportenmuziek.com/content_docs/mivawipawubumetuxuka.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=how+to+send+file+to+smart+tv
    • 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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b864.bin
c12a03a6480d0a74f0b597920d55cd9eeb1b17b30c88991f853b1d3f0944ccf3
pdf-font-stream PDF embedded font (sfnt) at offset 0xB864 16120 bytes
font_01_sfnt_off0000e1b5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE1B5 16792 bytes
font_02_sfnt_off0000f9cc.bin
e1adf33d64f4e9199d5f099c537d6fcca54f96e99b0a19597ff76ae04ba78823
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9CC 10656 bytes