Malicious PDF — malware analysis report

Static analysis result for SHA-256 19a4458ec4551ad4…

MALICIOUS

PDF

79.6 KB Created: 2021-08-07 23:04:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: eeb5d140fc0e69c70c9b4975fede7630 SHA-1: 0cd2315235d095425c7aba3d31ba5751a323447b SHA-256: 19a4458ec4551ad4a0fb6530866008503ad4ffbc28b368e2efe98ae175a78dd6
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to websites that appear to be compromised or disposable, suggesting a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is heavily obfuscated and unreadable, but the presence of multiple external URIs and link farm heuristics confirms the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://argentinaproduct.com/ckfinder/userfiles/files/2575352530.pdf In PDF document text
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/83f5808465711e7557bbe48ba7b52214/52603352493.pdfIn PDF document text
    • http://amadpich.com/userfiles/file/21612882208.pdfIn PDF document text
    • http://randoquad72.fr/userfiles/file/zivufesobigusazepemadi.pdfIn PDF document text
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610387014b111---xevedoxiwemir.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ee5c02d91de---zobosumunalox.pdfIn PDF document text
    • https://miguktour.com/FileData/ckfinder/files/20210714_561BB5B3E6A01F4B.pdfIn PDF document text
    • http://daotaoyduoc.org/wp-content/plugins/super-forms/uploads/php/files/rp2gbs6ksctik3nktuo6ujbovr/8545122973.pdfIn PDF document text
    • http://hzbmsj.net/images/upload/File/10596708430.pdfIn PDF document text
    • https://winston-woodward.com/wp-content/plugins/super-forms/uploads/php/files/3bb985ad15e18f3a201600fbffeaccdd/67574689800.pdfIn PDF document text
    • http://perchegouet.com/ckfinder/userfiles/files/9184889745.pdfIn PDF document text
    • http://wohingltd.com/userfiles/99678878923.pdfIn PDF document text
    • http://headrepublic.pl/images/files/fugoxukawalev.pdfIn PDF document text
    • http://gsxr.hu/userfiles/file/ruvopudupe.pdfIn PDF document text
    • http://aplus.to/userfiles/file/gipiw.pdfIn PDF document text
    • http://minhledtran.com/luutru/files/jesefewud.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/575d6ec820dd9592c8142a6e4cca9192/gunudereselulotinak.pdfIn PDF document text
    • http://sclifeguards.com/clients/16854/File/42144732399.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/1f8b9794cf634d24e34621cc4ff179bb/34892061539.pdfIn PDF document text
    • http://autohondl.cz/userfiles/file/panane.pdfIn PDF document text
    • http://gzky.cn/dubeite/ckfinder/userfiles/files/20210625_194832.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/8b6619748d0ef8e00849ed55191681a2/lafupanor.pdfIn PDF document text
    • http://itssilvertime.com/clients/2/24/24efe347a73a8ce028152bf895bc11a7/File/ridarIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=el+directivo+emocionalmente+inteligente+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_off0000cde0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDE0 18720 bytes
SHA-256: ae45aad9c51a01ec558ae26a1a876a46294521ceb168de30bcad8e7b165fb4f6
font_01_sfnt_off0000fd5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD5E 10844 bytes
SHA-256: d41e33a377960df9831a15156521b31e6a5f68e5f429f2e6e42d99f947eea514
font_02_sfnt_off00011623.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11623 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1