Malicious PDF — malware analysis report

Static analysis result for SHA-256 e7d83a19f02ac88f…

MALICIOUS

PDF

81.1 KB Created: 2021-09-13 16:53:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 3be777d9e0757a0ef41860649aa296be SHA-1: 4ea27c390dcbf82c7538a1ae637230a2e3483a13 SHA-256: e7d83a19f02ac88f8adff49c67e3ebe1662a49f61a4c54142c0c9d2d39cb2f02
174 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains multiple links to external PDFs hosted on various domains, suggesting it acts as a downloader or redirector. The presence of a 'download button' heuristic further supports the attack pattern of luring users into downloading a payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not 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
  • 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 http://alarm.pl/userfiles/file/mufozifuxumu.pdf In PDF document text
    • https://mebelihome.ru/upload_picture/digimimoto.pdfIn PDF document text
    • http://ramenzoni.eu/userfiles/files/56231721836.pdfIn PDF document text
    • http://vietdubai.com/userfiles/file/vugir.pdfIn PDF document text
    • https://bi-kiesabbau.de/cmsimple/images/file/rotikebafomufekivubim.pdfIn PDF document text
    • https://tw-itemaos.com/ckfinder/userfiles/files/judarujaruno.pdfIn PDF document text
    • http://redigonda.it/userfiles/files/gupinokugomedavab.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139f10ed401b---25473753872.pdfIn PDF document text
    • http://szyoujin.com/UploadFile/file/20210909183316054.pdfIn PDF document text
    • https://2ruoteexpo.it/ckfinder/userfiles/files/98606283060.pdfIn PDF document text
    • http://escuelasfutbol8.com/docs/files/werovopezusevobero.pdfIn PDF document text
    • http://refinerlink.com/userfiles/file/21682345517.pdfIn PDF document text
    • https://boucherienabli.com/uploads/FCK_files/file/kemaniwomu.pdfIn PDF document text
    • https://riwg.in/userfiles/file/5061684155.pdfIn PDF document text
    • https://o2opr.co/userfiles/files/beragavokipixerigitak.pdfIn PDF document text
    • http://eyela.kr/uploadfile/fckeditor/file/49510962960.pdfIn PDF document text
    • http://homeloanz.net/images/e/file/wosibizogexopupijuzul.pdfIn PDF document text
    • http://ambulatorioveterinariocigliano.com/userfiles/files/80115878352.pdfIn PDF document text
    • https://albertoangel.sinecsas.com/ckfinder/userfiles/files/bodafinewabosofetoledot.pdfIn PDF document text
    • http://veterinariacasettamattei.it/userfiles/files/11757535033.pdfIn PDF document text
    • http://adec-interiors.net/Uploads/file/96337659308.pdfIn PDF document text
    • http://metallpress.info/files/kuwanomafadet.pdfIn PDF document text
    • http://shortguycentral.com/ck_uploads/files/dazelumatimirufuw.pdfIn PDF document text
    • http://aapltd.net/userfiles/file/togirarabasavosubepozaf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=madout+car+parking+mod+apkPDF 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_off0000d235.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD235 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ea4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA4C 10696 bytes
SHA-256: ea41c85ad2b5f31add46dd48731ee57134d6dc5143cb22e8a60e718ce575d029
font_02_sfnt_off00010293.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10293 19772 bytes
SHA-256: 24a10f7946c30f5c258a72271326ded9104e97f2e097e03b1e1a6229c39a6d1b