Malicious PDF — malware analysis report

Static analysis result for SHA-256 236a8bb270f587f5…

MALICIOUS

PDF

81.3 KB Created: 2021-02-09 23:53:15 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: 58fa6dddafcec1e7fa1b02d1bcc6ca38 SHA-1: 24097effb9f30f820bac53937d1114f82c818826 SHA-256: 236a8bb270f587f5968aeb62e2cf998fe1ff9d88540b15fe554b78288d618f3e
192 Risk Score

Malware Insights

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

The PDF contains multiple links to external websites, with one specifically identified as a malicious redirector. The presence of a 'download button' heuristic and the ML classifier's high confidence score indicate a malicious intent to direct users to potentially harmful content. The document body, though heavily obfuscated, contains references that might be related to lures for VPN premium APKs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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
  • 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://crophysi.ru/aws?utm_term=aloha+vpn+premium+apk In PDF document text
    • https://kinigapiluxuke.weebly.com/uploads/1/3/4/8/134863840/pexusoj.pdfIn PDF document text
    • https://cdn.sqhk.co/zanaforare/gYjbghv/wizomu.pdfIn PDF document text
    • http://lnstagram-verifedbadge.com/business_administration_degree_required_classeswr550.pdfIn PDF document text
    • http://dorightunion.com/nezilubefalotefrmwd1.pdfIn PDF document text
    • http://lisolu.org/98738311994qtteh.pdfIn PDF document text
    • http://indital.fun/kifumilezisowazomotenofid5ij1.pdfIn PDF document text
    • https://cdn.sqhk.co/dokukavifig/hfx0jf3/pumaserulivogidixuzaneli.pdfIn PDF document text
    • http://just-gopro.com/pevigekalezorulude0xie0.pdfIn PDF document text
    • https://cdn.sqhk.co/duxadikoti/kudihij/23640747476.pdfIn PDF document text
    • http://rostov-mobile-doctor.ru/lucky_block_mod_minecraft_pe_free_download7u330.pdfIn PDF document text
    • http://goodsfor.life/251001931211uyzq.pdfIn PDF document text
    • http://waystep.site/alberta_infant_motor_scale_score_sheetxcvoo.pdfIn PDF document text
    • https://cdn.sqhk.co/vumuwilaj/ieWdhcY/14881221429.pdfIn PDF document text
    • https://fikobovivinuzo.weebly.com/uploads/1/3/0/7/130739062/nediki-ladul-karamosawixu.pdfIn PDF document text
    • https://tufanemoxidubux.weebly.com/uploads/1/3/4/3/134315727/batakatomudoloruxu.pdfIn PDF document text
    • http://kyhni.site/afcat_2020_notificationnxbrx.pdfIn PDF document text
    • http://soldonlittleton.com/archero_change_deviceqk9wz.pdfIn PDF document text
    • http://3bki.ru/ksp_and_molar_solubility_problems_worksheet_answersrie44.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://vidomolojo.epizy.com/xuleso.pdfIn PDF document text
    • http://vemusimovoxodan.rf.gd/17148290507.pdfIn PDF document text
    • http://rozopujonabesix.epizy.com/william_hogarth_primary_school_ofsted_report.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d585.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD585 4796 bytes
SHA-256: a56d743976f52b822ffba9f3d0aea2a2b0a0d6d0b686f588ee693fc2dee5ccdb
font_01_sfnt_off0000e591.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE591 1648 bytes
SHA-256: 4a8ebde5e94bd7e49bcaf164f77963ab18066d5334cf8871f4ac3f3f313d9c8a
font_02_sfnt_off0000edd4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDD4 11352 bytes
SHA-256: 6411d1d0db7a91a515f7699105413c87aa66f01b07ce8976e35ea415e0fcf7ad
font_03_sfnt_off00011469.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11469 16036 bytes
SHA-256: 354dce64f07f3d7acdf6a04edf763950ffbfec4edcbb4bfe17b65a83544077bb
font_04_sfnt_off000128d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128D1 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f