Malicious PDF — malware analysis report

Static analysis result for SHA-256 f52d8994ba74a98d…

MALICIOUS

PDF

74.9 KB Created: 2021-09-13 15:00:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 184e1923831ecd121bd922913fc07016 SHA-1: cc10a6938397509181e1dea900b877c55908d0f7 SHA-256: f52d8994ba74a98d223831dab4ba327d20bceb5f5636dbb8e241b333a2ca0934
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which are associated with link farms and disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is likely used to facilitate the redirection to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://wastran.ru/uplcv?utm_term=best+movie+app+for+kodi PDF link annotation
    • http://kelt.pl/userfiles/file/dawaxogepejenizalekago.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/16134d60f0fd41---7121389029.pdfIn PDF document text
    • https://jpjplumbingandheating.com/FCKeditor/file/96556988196.pdfIn PDF document text
    • http://xn--aknmedical-yub.com/uploads/file/83675853348.pdfIn PDF document text
    • http://jenan.com/ckfinder/userfiles/files/83046730540.pdfIn PDF document text
    • http://sxhk365.com/uploads/file///6904929129.pdfIn PDF document text
    • https://maviet.vn/upload/files/54013147665.pdfIn PDF document text
    • http://mylivediamondinventory.com/uploads/files/67427080441.pdfIn PDF document text
    • http://masterkontroll.hu/ckfinder/userfiles/files/16717101282.pdfIn PDF document text
    • https://silatur.com/js/ckfinder/userfiles/files/93907712313.pdfIn PDF document text
    • http://moscowballet.ru/userfiles/file/wawabugupiwufelaliv.pdfIn PDF document text
    • http://mecateengenharia.com.br/ckfinder/userfiles/files/48615591542.pdfIn PDF document text
    • http://vipforiraq.com/userfiles/files/44448509571.pdfIn PDF document text
    • https://alubiasdetolosa.com/files/galeria/files/96491325466.pdfIn PDF document text
    • https://zenithoverseas.com/assets/userfiles/files/nufekusilirufu.pdfIn PDF document text
    • http://mastervin.ru/files/file/25236420850.pdfIn PDF document text
    • https://olympicwroclaw.pl/zdjecia/fck/file/zivafixedomebugututawiv.pdfIn PDF document text
    • https://recapress.com/ckfinder/userfiles/files/12271038858.pdfIn PDF document text
    • http://studiofranzoni.eu/userfiles/files/32013356298.pdfIn PDF document text
    • http://lanaecoloridabruzzo.it/userfiles/file/4646588676.pdfIn PDF document text
    • http://mweb.cz/images/file/bebonamegibogefodit.pdfIn PDF document text
    • http://ahkkpcm.org/userfiles/janup.pdfIn PDF document text
    • https://betalinktech.com/blmedia/file/rikiniposefanizatagofede.pdfIn PDF document text
    • http://sten.kr/club/data/userfiles/file/20210909033725.pdfIn PDF document text
    • http://www.armstrongre.com/files/files/91344100434.pdfIn PDF document text
    • http://venusland.vn/app/webroot/img/files/bisagarebosus.pdfIn PDF document text
    • 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_off0000c166.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC166 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d978.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD978 17136 bytes
SHA-256: 00df5a4e804c7589073bf0c37a92627eedc58a78bdce6e50d564693dc5476574
font_02_sfnt_off0001053c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1053C 10720 bytes
SHA-256: 51936e07b611cfaca58c4d604467e75185e9d6f4a2f715c12bdf043d144529df