Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd58be3a9742d621…

MALICIOUS

PDF

78.1 KB Created: 2021-09-19 06:51:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8a0e0aa235781ba3a572d9d631e38507 SHA-1: 97684fbc91896b0f2f0eacf582881c107983ba78 SHA-256: cd58be3a9742d621e4aff8dfae36364cbce4c1d11f971155952eecb275e27e2e
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to domains that appear to be part of a link farm, as indicated by the PDF_SEO_DISPOSABLE_LINK_FARM heuristic. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of many unknown reputation URLs indicates a high likelihood of these leading to malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://robbes.nl/media/files/2028788502.pdf In PDF document text
    • http://sor1310.com/userfiles/file/97349710133.pdfIn PDF document text
    • http://neboskreb-irk.ru/uploads/userfiles/files/98611529895.pdfIn PDF document text
    • http://flapboxes.com/userfiles/files/vexapowewilidekifujeveg.pdfIn PDF document text
    • http://safarang.com/basefile/files/gesopurabewaxeran.pdfIn PDF document text
    • https://kuepancong.com/contents/files/fuvet.pdfIn PDF document text
    • http://acrclubinversores.com/files/galeria/files/73792006192.pdfIn PDF document text
    • http://sziszolg.hu/editor_up/28408447255.pdfIn PDF document text
    • http://zabradli-znerezu.cz/userfiles/file/lademonidogowe.pdfIn PDF document text
    • http://pobierzplik.pl/uploads/files/77606087256.pdfIn PDF document text
    • https://emenu.hu/editor_up/25361651255.pdfIn PDF document text
    • https://igruppe.no/ckfinder/userfiles/files/sovujiboluwevaxufimefan.pdfIn PDF document text
    • http://maimungkorn.com/UserFiles/file/73996683779.pdfIn PDF document text
    • https://turismopontevedra.com/ckfinder/userfiles/files/zogovozixakive.pdfIn PDF document text
    • https://trainova.com/userfiles/file/bazorivedizajonevabaxewi.pdfIn PDF document text
    • https://alkathirilaw.com/userfiles/files/9012985193.pdfIn PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/1613fcc02e0da3---puriduwedotunovo.pdfIn PDF document text
    • http://medicaldistri.com/ckfinder_files/files/90532679839.pdfIn PDF document text
    • http://stigstudiotecnico.it/userfiles/files/podixipibifopopi.pdfIn PDF document text
    • http://tcsklife.com/filespath/files/20210919091318.pdfIn PDF document text
    • https://irepairplus.nl/app/webroot/files/userfiles/files/51783285197.pdfIn PDF document text
    • https://cepatdaftargroup2.com/contents/files/78752297283.pdfIn PDF document text
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/9eb1ce0984accde864b15f0d86f1a723/rexijaninofewizisavakoz.pdfIn PDF document text
    • https://free-spirit-city.eu/uploads/wysiwyg/files/59915991314.pdfIn PDF document text
    • http://principessavencanice.com/wp-content/plugins/formcraft/file-upload/server/content/files/161469a5042532---41418044584.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=bach+prelude+violin+sheet+musicPDF 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_off0000cdea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDEA 17044 bytes
SHA-256: 290e29136cae6c78340492df27880de8abbb9ee4b0117fc2ed54835232ef5c6e
font_01_sfnt_off0000f98f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF98F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000111a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111A6 10996 bytes
SHA-256: 17486b747ebaa6f17680378c3323a02f3efc7efff643ebebf6913003fa4a3d36