Malicious PDF — malware analysis report

Static analysis result for SHA-256 d97af58b53283112…

MALICIOUS

PDF

75.7 KB Created: 2021-09-13 11:38:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: bf189ba87ab63aa023bab64f65036343 SHA-1: 71417e3b5f48cf266e71c25a16ffa448c6b2ed52 SHA-256: d97af58b532831122d4cf6e786aa629dd3cc0b079aa82306f69628ad66ceffa2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to potentially compromised websites or disposable hosting. The presence of multiple PDF-specific heuristics related to URI and link farms strongly suggests this document is designed to redirect users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://ww150001.linebot.net/upfile/files/20210908052905.pdf In PDF document text
    • http://krukaiart.com/userfiles/files/mixalen.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-9-5/20210905024837871075.pdfIn PDF document text
    • https://nyirfa.hu/uploads/files/tuxesadumigozulokafodi.pdfIn PDF document text
    • http://bogaarchitetti.it/userfiles/files/rutobine.pdfIn PDF document text
    • https://produktybhp.pl/pliki_user/File/xafizorepamesirewaxiwesu.pdfIn PDF document text
    • http://hc6999.com/userfiles/files/46286332040.pdfIn PDF document text
    • https://stop-remont.ru/ckfinder/userfiles/files/66143074026.pdfIn PDF document text
    • http://markasib.ru/ckfinder/userfiles/files/tawawomumanivotode.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c73f9b92f0---vatokoluvalarenebu.pdfIn PDF document text
    • http://gzperson.com/uploadfile/files/38443979020.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16134fe3ae3b96---87848919935.pdfIn PDF document text
    • https://magatek.com/documents/file/tefare.pdfIn PDF document text
    • http://summitremodelinginc.com/userfiles/files/jafojaz.pdfIn PDF document text
    • http://newworldss.com/uploads/file/4867646949.pdfIn PDF document text
    • http://loaamtran.com/files/usersfiles/files/pifotajelepovibiju.pdfIn PDF document text
    • http://www.gamylai.vn/uploads/files/90629338793.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613252380d96d---78338001859.pdfIn PDF document text
    • https://kindeeyudee.com/ck_files/files/wegezijam.pdfIn PDF document text
    • https://giyimkent.formenemlak.com/upload/ckfinder/files/kisedikibe.pdfIn PDF document text
    • https://securitydm.com/slicice/file/12245203689.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=clark+creative+education+answer+key+pdfPDF 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_off0000c1dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1DD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d9f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9F4 11100 bytes
SHA-256: 2312420762f724e472aaca1c7ade03a9f3e8efe60783e4817b0dafeb002afa71
font_02_sfnt_off0000f40f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF40F 17932 bytes
SHA-256: ae6ca16297eb0e81f45aa934f88e03d98bb9e4b88dd1cd4a773fadf8819f49e0