Malicious PDF — malware analysis report

Static analysis result for SHA-256 591d473be8dd3ea9…

MALICIOUS

PDF

99.3 KB Created: 2021-04-10 19:06:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 25ecdfc3db6a4f46e32fc492f35dc815 SHA-1: 973f2bf4b09815ccf24586ee453d394d3cab3540 SHA-256: 591d473be8dd3ea933a5df5e6007b91ac8e6a670d50bdc0054fbfd0f5deb40f0
206 Risk Score

Malware Insights

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

The PDF file exhibits characteristics of a link farm, with numerous external URIs pointing to disposable hosting. Heuristics indicate malformed exploit streams and a high ML classification score, suggesting malicious intent. The primary URL, https://gimoguvi.ru/strik?utm_term=agile+scrum+software+development+process, appears to be a redirector for SEO manipulation or potentially to distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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
  • 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.
  • 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.
  • 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://gimoguvi.ru/strik?utm_term=agile+scrum+software+development+process PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4375342/normal_602c4ff8568f3.pdfIn PDF document text
    • http://rowowevu.mypressonline.com/tratamiento_para_absceso_cutaneo.pdfIn PDF document text
    • http://povulofi.mywebcommunity.org/jemikex.pdfIn PDF document text
    • https://cdn.sqhk.co/fejovuwov/cjfhhuS/rifizivatefezot.pdfIn PDF document text
    • https://fadufavibog.weebly.com/uploads/1/3/4/8/134889314/malomezub.pdfIn PDF document text
    • https://cdn.sqhk.co/zajujuva/i6gi8xG/63963449910.pdfIn PDF document text
    • https://cdn.sqhk.co/zuvifilezaja/QgcppmE/popirufatevumuv.pdfIn PDF document text
    • http://newuwedeza.mypressonline.com/4382620614.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4415935/normal_5ff0e3f93edb0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4466161/normal_600f292846eed.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4466173/normal_5fe240ce7af7c.pdfIn PDF document text
    • https://cdn.sqhk.co/mibupufek/meidugf/mega_mall_story_2_mod_apk_android_1.pdfIn PDF document text
    • https://cdn.sqhk.co/kataregulu/jvMP7aO/spiderman_hd_wallpaper_for_mobile.pdfIn PDF document text
    • https://cdn.sqhk.co/xegunorasu/nlieggY/battle_for_the_galaxy_le_mod_apk_download.pdfIn PDF document text
    • https://cdn.sqhk.co/fopikudapom/zgihcWt/xaxilafobozelexo.pdfIn PDF document text
    • https://cdn.sqhk.co/xafukapewe/gKiggei/22537771985.pdfIn PDF document text
    • https://wewokidopubix.weebly.com/uploads/1/3/0/8/130873978/bamudirugazobid_wixajusi.pdfIn PDF document text
    • https://gugekeki.weebly.com/uploads/1/3/4/3/134374678/fekivike.pdfIn PDF document text
    • https://xiridibokolu.weebly.com/uploads/1/3/1/3/131379099/wowamivunigelulomob.pdfIn PDF document text
    • http://lanasobewusek.22web.org/peek_biomaterials_handbook.pdfIn PDF document text
    • https://tujiniwiko.weebly.com/uploads/1/3/5/3/135350236/melexup_mepid_xebipukut_wefogom.pdfIn PDF document text
    • http://tufuwavaziga.mygamesonline.org/luxilakokafuj.pdfIn PDF document text
    • http://tometifo.getenjoyment.net/mokazunelaloxinutodo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://wovutemikinodow.rf.gd/ak_47_gun_sound_ringtone_free.pdfIn PDF document text
    • http://luzazawa.rf.gd/ninumalexedisegagoga.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000146ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x146ED 5616 bytes
SHA-256: 80f8a3cebe3bfa1ec381354d945f2578a7e31d2301d1ff7353c64bd6a0d10d4b
font_01_sfnt_off00015a14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15A14 11104 bytes
SHA-256: 52d54ae7a0bbfd81e4e34a48357b6c6adbfff1da205a9b53a80369642ae1a497