Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a65d51a18834c5f…

MALICIOUS

PDF

91.6 KB Created: 2021-09-27 01:52:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 71bf684cc75786cac190ac8ae6e90c50 SHA-1: 7507ce09005bc7e965dca5dd397a17fcd08d7326 SHA-256: 9a65d51a18834c5fde9437c7db36b2e22acd57208ef6b665082630d774b21583
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to PDF files on disposable hosting, suggesting a link farm or phishing lure. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags this behavior. While no scripts were explicitly extracted, the presence of embedded URLs and the overall structure strongly suggest an attempt to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9786

Heuristics 6

  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://queure.ru/uplcv?utm_term=najbolje+teme+za+android PDF link annotation
    • http://castel.lu/userfiles/files/loneduwonewitopaguzisin.pdfIn PDF document text
    • http://cw-cut.com/uploads/file/gezuw.pdfIn PDF document text
    • http://okgwa.net/50/files1/file/xoxaludedixojige.pdfIn PDF document text
    • http://85560891.com/upfolder/e/files/20210903152521.pdfIn PDF document text
    • http://bkdesign.ee/userfiles/file/suzikujajiredijugux.pdfIn PDF document text
    • https://96662888.com/editor_upload/file/kuzobevaserejivexazaruwu.pdfIn PDF document text
    • http://grgct.com/ckfinder/userfiles/files/51953483205.pdfIn PDF document text
    • http://waxiangyuan.com/upload_fck/file/2021-9-4/20210904043752708653.pdfIn PDF document text
    • http://centromp.it/userfiles/files/1231579527.pdfIn PDF document text
    • https://dubaimotorcycletours.com/uploaded_images/files/74496163071.pdfIn PDF document text
    • http://principessavencanice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f7fbe76412---fubudexosalezud.pdfIn PDF document text
    • http://macautemple.com/userfiles/file/fixidanelafatupogugeli.pdfIn PDF document text
    • http://accessibilite-salle-eau.com/ckfinder/userfiles/files/14662429018.pdfIn PDF document text
    • https://rubenferro.com/userfiles/file/93129511141.pdfIn PDF document text
    • https://alcc.c-zentrix.com/ALCC/mail_attachments/multitenant-ws-01/1/1631848229.pdfIn PDF document text
    • http://vinacafe-dalat.com/Images_upload/files/maberokose.pdfIn PDF document text
    • http://tinhdauvietnam.vn/upload/files/nepowutifodafojufam.pdfIn PDF document text
    • https://salwangurugram.com/files/babogavobifodokuvofilobup.pdfIn PDF document text
    • http://sungsam.net/userData/board/file/77102066233.pdfIn PDF document text
    • https://fasleh.net/Files/files/38823071655.pdfIn PDF document text
    • https://gres-k.cat/userfiles/file/gotiramupatazuzituxuxezeg.pdfIn PDF document text
    • http://residencecarlofelice.com/userfiles/files/tonoginilonux.pdfIn PDF document text
    • https://ip-pharma.net/data/files/liwilumefonagasotavatadeb.pdfIn PDF document text
    • https://8foro.exceltur.org/exceltur_nuevo/ckfinder/userfiles/files/10137769630.pdfIn PDF document text
    • http://zuche0551.com/upload/file/miziwekidagixewimuf.pdfIn PDF document text
    • http://piqiso.ru/userfiles/file/zufifiwedejob.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e7f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7F5 17676 bytes
SHA-256: 228d248393cd56d2df14a06755340a7ec1cb9d431bf75ea03f466976180a50d5
font_01_sfnt_off00011478.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11478 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012c8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C8F 10548 bytes
SHA-256: 7364ff9a014cbe4dad87a6a964ef1162e7aeea0af52f90cae50f441019c14821
font_03_sfnt_off00014481.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14481 17484 bytes
SHA-256: 32cf6784732c215737b2352225a0e03f6497cf745d1cd8a9691abdb54074ff55