Malicious PDF — malware analysis report

Static analysis result for SHA-256 f979f6f850013ad8…

MALICIOUS

PDF

73.5 KB Created: 2021-09-25 02:29:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 8174d576d3f0df90dff9aa6196a12c15 SHA-1: 1814fe41b94e36ad73e181ea2320b3bb81f1043a SHA-256: f979f6f850013ad8e5578eb0d965b65cf12a209496a318b49c2a9446018bfad1
126 Risk Score

Malware Insights

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

This PDF was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The presence of numerous external links, many pointing to disposable domains, suggests a link farm or SEO poisoning tactic. The document body is heavily obfuscated, preventing a clear understanding of its direct payload, but the overall structure and heuristic firings point towards a phishing or content distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://curtain.jinware.com/upload/files/vimudukozuguditu.pdf In PDF document text
    • https://branchennachweis.eu/userfiles/file/79308821668.pdfIn PDF document text
    • http://picart-personal.pl/fckupload/upload/file/78616320413.pdfIn PDF document text
    • http://telek-trans.hu/editor_up/luzofakowim.pdfIn PDF document text
    • http://ybshajiang.com/userfiles/file/2021-09-01/210901084412503640wvgzzcui98ft.pdfIn PDF document text
    • https://beautydiction.com/ckfinder/userfiles/files/jepilajejerexewodarituke.pdfIn PDF document text
    • https://udruga-invalida.hr/files/pizuva.pdfIn PDF document text
    • https://armour-technoz-ca.otzol.net/ckfinder/userfiles/files/sovuf.pdfIn PDF document text
    • http://otelm4b.ru/admin/ckfinder/userfiles/files/ligifeb.pdfIn PDF document text
    • http://alconsprom.ru/ckfinder/userfiles/files/2041510528.pdfIn PDF document text
    • http://apicn.net/upload/files/94736797687.pdfIn PDF document text
    • https://sagarexpress.com/userfiles/file/giwonifupig.pdfIn PDF document text
    • http://teraval.cz/res/file/kupefudevikurejum.pdfIn PDF document text
    • http://erdbau-rauch.at/fagusixol.pdfIn PDF document text
    • http://futimisdev.com/userfiles/file/tijiniladomopufejusov.pdfIn PDF document text
    • https://eseninternational.com/uploads/files/13073181707.pdfIn PDF document text
    • http://khamranghaiphong.com/upload/files/lozopevadikutefoxomomo.pdfIn PDF document text
    • https://nhatngudongkinh.com/upload/ckupload/files/xifos.pdfIn PDF document text
    • http://kaiyudachem.com/filespath/files/20210911122450.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/h3fgba00js6ne2918ehs8ko4nn/bejopumapatakasafita.pdfIn PDF document text
    • https://ezokniga.com/uploads/file/mixazavaremavife.pdfIn PDF document text
    • http://npi-management.org/ressource/site-image/files/gimopizosilirejoju.pdfIn PDF document text
    • http://abpjseah.news-read.com/upload/files/39570492253.pdfIn PDF document text
    • https://digireg.es/upload/781433761.pdfIn PDF document text
    • http://tns-china.cn/editor_upload_image/file/tiwane.pdfIn PDF document text
    • http://law885995.com/upload/fckimages/file/dipojimimopubodugixonu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=set+my+phone+back+to+factory+settingsPDF 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_off0000b603.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB603 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ce1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE1A 11304 bytes
SHA-256: ae64476bff2cdbb908ff2ba4ad40eba366afae138248ce14708020d1cb8593ee
font_02_sfnt_off0000e844.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE844 18868 bytes
SHA-256: 1f5706cf8c96f2ff72abe4f60b24fac11cf4b05a05bbd8a1bc9b8dcc3be355d7