Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b61ea64570814d5…

MALICIOUS

PDF

84.1 KB Created: 2021-09-11 14:11:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 191e4d5e6dd72003905baf2697b042b2 SHA-1: 9906a176af093bcaf5776b3cf5804a4039a4fe61 SHA-256: 1b61ea64570814d5a85bb21bfdd129d828133a8464de6a90c0617ac6789b57ee
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to other PDF files hosted on disposable domains, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a phishing or malware delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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 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 https://www.gullyracing.it/admin/ckfinder/userfiles/files/55181820525.pdf In PDF document text
    • http://shsuorui.com/uploadfiles/fckeditor/20210901/file/16304873062557.pdfIn PDF document text
    • http://boissee.fr/userfiles/file/tudovedemegimufeket.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/16134cb1d91153---80987669227.pdfIn PDF document text
    • http://tydafa.com/dafa/uploadfiles/20210908031434.pdfIn PDF document text
    • http://terralis.net/catalogue_dynamique/file/tisafekagofidosizowufos.pdfIn PDF document text
    • https://jv-cms.crazy-jessie.nl/uploads/files/23214037057.pdfIn PDF document text
    • http://skulpt.in/admin/uploads/file/20437694496.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/vemapijozawuzabemiga.pdfIn PDF document text
    • http://bielle-srl.com/userfiles/files/lolasorutogixanekapa.pdfIn PDF document text
    • http://a-pro-peau.fr/userfiles/file/lizalemugekem.pdfIn PDF document text
    • http://goldendoodlesofthesierranevadas.com/userfiles/file/56551095548.pdfIn PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/1613090b4d2ea0---zivutumor.pdfIn PDF document text
    • http://fotografieindex.nl/images/uploads/govizuwivasadewemunakov.pdfIn PDF document text
    • https://hizlipin.com/calisma2/files/uploads/bupixax.pdfIn PDF document text
    • http://elai.kz/upload/2021/09files/210911155950873168aagnw.pdfIn PDF document text
    • http://metalzilembo.it/userfiles/files/kidumoz.pdfIn PDF document text
    • http://thedewakohchang.com/image/upload/File/utam.pdfIn PDF document text
    • http://tyros-club.de/userfiles/file/22629974903.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/161362d5a2df96---98363233302.pdfIn PDF document text
    • https://giyimkent.formenemlak.com/upload/ckfinder/files/wilunadakazonusumaj.pdfIn PDF document text
    • https://zagi.hr/files/nidugovumobadu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=blackmart+pro+apk+free+downloadPDF 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_off0000e2e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2E3 10752 bytes
SHA-256: 1ac882a2aa2c5c2712828fd8c2a582060cacca51fde65532450ddb934a72162c
font_01_sfnt_off0000fbbc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBBC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000113ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113CE 18268 bytes
SHA-256: 890ddbf08e37705a24d54269807ce1a1ca6e3adefdfb028e258d8bcdcbc754ff