Malicious PDF — malware analysis report

Static analysis result for SHA-256 31ed9dd79051f173…

MALICIOUS

PDF

78.5 KB Created: 2021-03-08 22:11:05 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 6df6fba239cead25793a228671597f1d SHA-1: 7ec07475d21273694db3a4c29b194d9f9131bbc2 SHA-256: 31ed9dd79051f1732969350a1c3e8d9504daa37d19602065683176da6fb08ccb
194 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of external links, many hosted on disposable domains, suggesting a link farm designed to distribute malware or phish users. The presence of a 'download button' heuristic further supports a malicious download lure. ClamAV detection and ML classification confirm the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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 contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://nipisod.ru/123?utm_term=android+one+ui+samsung+apk PDF link annotation
    • https://begukuji.weebly.com/uploads/1/3/4/8/134880386/ribekatul_kagoxima_womorofodoju.pdfIn PDF document text
    • https://cdn.sqhk.co/veludewozen/idDKJhh/colors_tv_serial_ringtones_free_download.pdfIn PDF document text
    • https://sosabugipos.weebly.com/uploads/1/3/4/6/134657522/bagapufu_gobuwodim_netiwopaxesener_jabomaxa.pdfIn PDF document text
    • https://cdn.sqhk.co/jesupasuzoku/Ijhhhje/11655937405.pdfIn PDF document text
    • https://cdn.sqhk.co/pofaxiniraz/ebFpBhb/diletemiwab.pdfIn PDF document text
    • https://jowadukezivi.weebly.com/uploads/1/3/1/3/131379295/ab5975cc1b4e4c6.pdfIn PDF document text
    • https://cdn.sqhk.co/fafovewidom/bYjeifh/63500142774.pdfIn PDF document text
    • https://cdn.sqhk.co/dikizumi/heVeIjh/sky_baron_war_of_nations.pdfIn PDF document text
    • https://cdn.sqhk.co/baxorurifina/LhhjIwE/59425408236.pdfIn PDF document text
    • https://cdn.sqhk.co/letonolomo/FhhKih5/xefisogirur.pdfIn PDF document text
    • https://cdn.sqhk.co/gabisolovima/7pKd0if/red_button_up_dress_collar.pdfIn PDF document text
    • https://tetarexaxamos.weebly.com/uploads/1/3/1/4/131483090/ef83e6219b3a21.pdfIn PDF document text
    • https://dekukosozo.weebly.com/uploads/1/3/1/0/131070054/0baece986797.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://8767aa75-4bd5-48c0-94ca-24e983238001.filesusr.com/ugd/debdc1_5c4d750bcd014f64850cf2da4b92f841.pdf?index=trueIn PDF document text
    • https://933afb0c-60ca-4ff4-ba38-e7c804ca925d.filesusr.com/ugd/941881_7bb7b2ae21274d4d9b7c6395f698be45.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/5ce15dac-5425-4b6f-955d-efdfbb9cc49b/62508746780.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/87e84fb1-94db-4e8f-b996-26f141314d00/resnick_halliday_krane_physics_volume_2.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f9e5792e-ce7b-4e80-acb2-e5eb703a580d/cant_stop_wont_stop_concealer_beige.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0f659ef8-c429-48d8-8704-c82975a7a637/50591845430.pdfIn PDF document text
    • https://8b8c7005-3af0-45a1-8e5b-a6902caa9335.filesusr.com/ugd/dbd7d9_22a6edc0ad5f42aba9593aadb2984a72.pdf?index=trueIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f4d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4D8 5300 bytes
SHA-256: 708cb9b575ec3bb4e373422acc15910afcb97ff4621143b862058a9083a09a10
font_01_sfnt_off000106cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106CC 12072 bytes
SHA-256: 123833f043817071e29992ae54e60b514c61bea643e4d4fad4c0aa91813e53e3