Malicious PDF — malware analysis report

Static analysis result for SHA-256 9fbd7d77e04790af…

MALICIOUS

PDF

79.4 KB Created: 2021-09-17 16:51:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0093b043d605a056e261a900ee646e72 SHA-1: 2bd5ba276e0347b7bbe6ab13d8dea4b000f5c858 SHA-256: 9fbd7d77e04790af3ffbe84423dc7ccb1c8a32b0175de2cba660d8faee212e1a
196 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware delivery. No scripts were extracted, but the PDF structure itself facilitates the redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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 link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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 https://infrive.ru/uplcv?utm_term=change+background+on+messenger+video+call
    • http://elskenecologie.nl/files/39011768258.pdf
    • http://sonnenheizungen.ch/fckeditor/editor/images/file/vetujureb.pdf
    • http://kompassztuki.pl/Image/files/21795443962.pdf
    • http://edu-soft.ru/site/htmlimages/file/35675071638.pdf
    • http://klawiatury-foliowe.pl/_data/file/wigilemajewiselixiti.pdf
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/16131914caf8ea---78387621757.pdf
    • https://a-guskov.ru/uploads/files/40698592078.pdf
    • http://hiroshima-teishaku.com/userfiles/file/boxuwibekulusafepepevot.pdf
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/2c576622e4ba2ed284c77ceb2859fb62/36840608825.pdf
    • http://www.asiacoservice.com/file/files/77339261406.pdf
    • http://innospectrum.eu/hirlevel/file/53240120668.pdf
    • https://magic-ray.shop/uploads/files/83001535126.pdf
    • http://gaziogluenerji.com/images_upload/files/87788262870.pdf
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131d67f25252---56290809372.pdf
    • http://stagegator.scorchmark.com/stagegator/ckfinder/userfiles/files/63610724376.pdf
    • https://1000families.eu/userfiles/file/vakurexozujopukakisonod.pdf
    • http://keemunblacktea.cn/uploads/file/081747057739.pdf
    • https://manage3.realtourvision.com/rtv/ckfinder/userfiles/images/files/wogumodesijezobufa.pdf
    • https://vokalensemble-vocembalo.ch/userfiles/file/7541338618.pdf
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/eaaf677d735ac7d41dbb0e87401ed97a/fexikojuf.pdf
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/161308d4538afa---taxugudowovotedozovud.pdf
    • https://promoxcenter.ro/ckfinder/userfiles/files/virisixek.pdf
    • http://showpalmedical.com/userfiles/tisedutegifekevawexuvufom.pdf
    • http://seritour.com/rsm/files/27922864679.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/gpcqlhplqsfvacgetur0fni3n1/mudewobipubedexerosoludo.pdf
    • http://novelinternationalschool.com/ckfinder/userfiles/files/rawatijetejagodimajegipe.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://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_off0000d158.bin
0420cd6795efb6bc74ac271821f049b6c0bea4aed6bba8675453298bc165c6fe
pdf-font-stream PDF embedded font (sfnt) at offset 0xD158 17176 bytes
font_01_sfnt_off0000fdad.bin
523afbe54facc95a5c454d5bb072ebe941efeae879850be99573ce6b0a78c585
pdf-font-stream PDF embedded font (sfnt) at offset 0xFDAD 11148 bytes
font_02_sfnt_off00011752.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11752 16792 bytes