Malicious PDF — malware analysis report

Static analysis result for SHA-256 73bb46a4b8bdb0eb…

MALICIOUS

PDF

72.5 KB Created: 2021-09-26 02:45:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: abe081f782197d1242b3758440a87937 SHA-1: 7c07b0744730af69e38c24b4ba5fd706fcf3dcd6 SHA-256: 73bb46a4b8bdb0eb3025a970bdd2130ff3bd36232d2fbbe174516ed5973e273c
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links to external resources, many of which are hosted on disposable domains and appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to trick users into downloading further malicious content. The presence of embedded URLs and the PDF_RANDOM_URL_LINK heuristic suggest an attempt to distribute malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 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.
  • 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://restokrat.info/userfiles/file/jikawifokogolulomat.pdf In PDF document text
    • https://avphunter.ro/ckfinder/userfiles/files/koganuneloraveriguw.pdfIn PDF document text
    • http://quangcongluc.com/upload/files/jikimitanidew.pdfIn PDF document text
    • http://www.rarlaw.net/siteuploads/editorimg/file/47550949465.pdfIn PDF document text
    • http://dochoiotovn.com/uploads/userfiles/file/86057809827.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/0c3e9348d1265db1a78f890e5d0ee23a/33678430660.pdfIn PDF document text
    • https://madame-tina.com/ckfinder/userfiles/files/65711429931.pdfIn PDF document text
    • https://phuquiland.com/upload/files/43793368147.pdfIn PDF document text
    • http://kolesnikov.pro/ckfinder/userfiles/files/waweso.pdfIn PDF document text
    • http://indago-rovigo.it/userfiles/files/42583150951.pdfIn PDF document text
    • https://hoakhanh.vn/uploads/image/files/wadajomaladotuzovolimow.pdfIn PDF document text
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d2e6c406db---2377892487.pdfIn PDF document text
    • http://ave-france.com/pics/files/niwufibokarodisazorig.pdfIn PDF document text
    • https://gbagencement.fr/uploads/file/1112924969.pdfIn PDF document text
    • http://cottoneauto.it/userfiles/files/vonosuvanezeba.pdfIn PDF document text
    • http://newshop.jp/archive/file/pokovamerat.pdfIn PDF document text
    • http://infrabud.eu/fckpliki/file/sakidologolonozobigi.pdfIn PDF document text
    • https://braindevelopmentmaps.org/userfiles/files/badufow.pdfIn PDF document text
    • http://cutskytools.com/d/files/68314669334.pdfIn PDF document text
    • http://papianiarch.it/userfiles/files/39677577376.pdfIn PDF document text
    • http://ambulatorioveterinariosanfrancesco.com/userfiles/files/xifeme.pdfIn PDF document text
    • http://cambresisemploi.fr/ckfinder/userfiles/files/koximanarumun.pdfIn PDF document text
    • http://pate4me.com/userfiles/file/xewegefir.pdfIn PDF document text
    • https://marljivo.hr/userfiles/file/muronunepoxiwudi.pdfIn PDF document text
    • http://boschvietnam.vn/files/usersfiles/files/zoterumajewezuxujut.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=my+hero+academia+heroes+rising+full+movie+123PDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b4bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB4BF 11440 bytes
SHA-256: 0537148834dec2aea0957bc856e7f36e939012bd69ef85205f4fd0d496509401
font_01_sfnt_off0000cf86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF86 16952 bytes
SHA-256: 0717e95bcbfdf369afb73fb9b9b4f875adc3766f5f2cec859b654ab228724352
font_02_sfnt_off0000fabd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFABD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1