Malicious PDF — malware analysis report

Static analysis result for SHA-256 57a6f9fbb8ca5a15…

MALICIOUS

PDF

85.4 KB Created: 2021-09-10 19:52:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 4325f710ad98568cc6692fae0c2588c8 SHA-1: 60c1cd6aa0b6082cc377ca1ef54ea3a62abb5030 SHA-256: 57a6f9fbb8ca5a1572cffa666b19eaee29731351825fa5d9db6ff99c0f6f2e96
176 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm. Multiple heuristics indicate the PDF contains numerous links pointing to compromised or disposable domains, suggesting an attempt to lure users to malicious content. The presence of external URIs and link farm indicators strongly supports a phishing or malware distribution attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://cerritos.songhakbbq.com/uploads/files/14898067929.pdf In PDF document text
    • http://cka-shiba.com/ckfinder/userfiles/files/22800626264.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161317fbdad391---runodevizokuvuba.pdfIn PDF document text
    • http://dailygiasi.com/uploads/userfiles/file/88953006813.pdfIn PDF document text
    • https://aathichudi.org/userfiles/file/rumivenobusajifigemazan.pdfIn PDF document text
    • https://xrtradingfeedback.com/cmsimages/file/32753222482.pdfIn PDF document text
    • http://omatsuri.kr/data/userfiles/files/wanokazul.pdfIn PDF document text
    • http://nwhouse.ru/uploads/file/xixekufa.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/rukuduso.pdfIn PDF document text
    • http://etpatatietpatata.com/userfiles/files/nifalitedeboraxajisoti.pdfIn PDF document text
    • http://alpinedelhi.com/userfiles/files/mivag.pdfIn PDF document text
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/16136aa3c0dda2---winawejoditakirukijoras.pdfIn PDF document text
    • https://www.andreivieru.com/ckfinder/userfiles/files/jadalafudasijolorex.pdfIn PDF document text
    • https://horacebatten.com/ckfinder/userfiles/files/tovufitapolixef.pdfIn PDF document text
    • http://ziguratex.com/helpdesk/app/webroot/img/userfiles/files/80595618873.pdfIn PDF document text
    • http://3wsystems.com/shipinc/userfiles/files/53556629289.pdfIn PDF document text
    • http://nhuaduongnhapkhauaz.org/upload/files/naradimekap.pdfIn PDF document text
    • http://georgekoldun.com/var/upload/file/12875711560.pdfIn PDF document text
    • http://bangiyaparishadtoronto.ca/bpt/editor/uploadfiles/fegejelenivilifapuseja.pdfIn PDF document text
    • http://smartdeal.pl/files/upload/files/tufemukonox.pdfIn PDF document text
    • http://bagandpack.ru/wp-content/plugins/super-forms/uploads/php/files/39ecfd381823cf1adf3d1665972086f4/66403941370.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=stream+from+android+to+ipadPDF 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_off0000e7a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7A8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ffba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFBA 18800 bytes
SHA-256: 0782d78ade58f91748325568eec6fc5f7ac9b0091f71f02e4682e17d2930fb77
font_02_sfnt_off00013050.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13050 10520 bytes
SHA-256: b1c1268a227549f135bb94aeb6aae7c5eaef8d1cf7c4d8ecb2912fb385402772