Malicious PDF — malware analysis report

Static analysis result for SHA-256 84c251ecf946e05b…

MALICIOUS

PDF

73.5 KB Created: 2021-09-20 00:23:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 39bb4ad5e69ee0a9346a029fc75b08d6 SHA-1: ef4ee5cc17263d51b6318d100565da9ea5cf8d6b SHA-256: 84c251ecf946e05bf2de66c699f29ab55f5df648b79928945de478d47facecaf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous external URLs, many of which are part of link farms on disposable or compromised hosting, suggesting a phishing or malware distribution scheme. The presence of embedded URLs and the PDF structure point towards an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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 https://infrive.ru/uplcv?utm_term=craftsman+mod+apk+skin
    • http://lerucherdesanges.fr/userfiles/file/54272267179.pdf
    • https://pre-www.bridge-college.com/uploaded/ckeditor/files/27162673905.pdf
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/161435a85ea2fa---41295656992.pdf
    • http://forma8.kz/ckfinder/userfiles/files/zuzekimipomidomi.pdf
    • http://walosports.cl/userfiles/file/zirajoraf.pdf
    • http://delta-serwis.pl/pliki/nusafetubaramepene.pdf
    • http://bastola.org/userfiles/file/xobosajabakizituvebe.pdf
    • http://www.dogwoodagility.nl/ckfinder/userfiles/files/7683542204.pdf
    • http://seidels-mineralienwelt.de/images/uploaded/file/nurekajalafokajaniwosa.pdf
    • https://signos.larrialdiak.es/files/galeria/files/75004312670.pdf
    • http://ratchadatitan.com/UserFiles/File/80234446626.pdf
    • https://psystat.net/candyticket/uploads/page_images/files/gofukazo.pdf
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/bda16a39be6e8508b7f51972ab392a88/fogepu.pdf
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/c3542cc294774d76e1c581f683acc16e/94449004583.pdf
    • http://zeshengtecphar.com/UploadFiles/FCKeditor/20210902011316.pdf
    • https://conexkarvan.com/cache/fck_files/file/pumemoxigo.pdf
    • http://www.pzkexie.com/up_files/file/81642486602.pdf
    • http://studioarchoggianiepartners.it/userfiles/files/wuwevezosularitigilewako.pdf
    • http://studiotecniconuti.it/userfiles/files/32355776816.pdf
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1614404027650d---49313000237.pdf
    • http://delta-serwis.pl/pliki/sunepogozesizika.pdf
    • http://vektor-bezpeki.com/userfiles/files/76867090425.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_off0000bfe8.bin
48283c0e33b5139c0b007944d6d7e024f0b0798ea9efb1a935bea117705f1002
pdf-font-stream PDF embedded font (sfnt) at offset 0xBFE8 16008 bytes
font_01_sfnt_off0000e8a4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE8A4 16792 bytes
font_02_sfnt_off000100bb.bin
d17dd7f6e60a293a0cac5c03fa67b2ae289275499b7c7b0966518107bacc073f
pdf-font-stream PDF embedded font (sfnt) at offset 0x100BB 10604 bytes