Malicious PDF — malware analysis report

Static analysis result for SHA-256 e8f3878a70de263c…

MALICIOUS

PDF

80.2 KB Created: 2021-09-19 11:48:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 0d57f0ab763ffa33ff57d46cb93f0c8e SHA-1: 732c8917853affdf482c672a254870bd457a9f49 SHA-256: e8f3878a70de263c99275e20c1929ee083fd6c4862b5fef485047e72de0ea7c4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised or disposable domains, indicating a link farm or redirection scheme. Heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly suggest this malicious intent. The ML classifier and ClamAV detection further confirm its malicious nature, likely as a phishing or SEO spam lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://yyfxsw.com/upload/files/58553300176.pdf In PDF document text
    • http://www.nomorcantikjoss.com/file/80030385755.pdfIn PDF document text
    • http://lsmtrontractor.com/upfiles/file/20210901235734.pdfIn PDF document text
    • http://caerulumpharma.com/upload/files/rimaxajoxuxezavajilap.pdfIn PDF document text
    • http://thuaphatlailongthanh.vn/upload/contentFile/minhchau/file/49639743323.pdfIn PDF document text
    • https://jpt.mysmartedu.com/uploadimages/files/lisagurubogofawisumusid.pdfIn PDF document text
    • http://vipnovini.bg/root/f/uploads/files/17116041436.pdfIn PDF document text
    • https://cmfnepal.org/userfiles/files/68962202021.pdfIn PDF document text
    • http://myblindz.com/fck_user_files/file/nageno.pdfIn PDF document text
    • http://classtool.info/upload/files/wolufab.pdfIn PDF document text
    • https://ags-car.60km.com/upload/files/41044707434.pdfIn PDF document text
    • https://qatarsecurityservices.com/public_html/userfiles/file/4822155871.pdfIn PDF document text
    • https://mk-sito.it/uploads/file/lubari.pdfIn PDF document text
    • http://avtokit116.ru/!upload/files/sudejewoxixitefonitid.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613f70611f5b2---62211431878.pdfIn PDF document text
    • http://thainightjob.com/ckfinder/userfiles/files/wofekulafebexed.pdfIn PDF document text
    • https://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/9a23bfbf27c4d8f947a8ff14efbfd0ad/kiwowamor.pdfIn PDF document text
    • http://sxsasa.org/images_fck/file/1630972253.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/161373670990cf---valenotunimajelafitiki.pdfIn PDF document text
    • https://apluskleaning.com/admin/images/file/28947322174.pdfIn PDF document text
    • https://huanghecables.com/d/files/38396701617.pdfIn PDF document text
    • http://www.hkrns.org.hk/ckfinder/userfiles/files/fuguf.pdfIn PDF document text
    • https://fleschimmo.lu/userfiles/files/nifunivazepiwu.pdfIn PDF document text
    • http://alatasfilms.gr/ILC/img/file/kefogebitezuponaxa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=best+emulator+of+free+firePDF 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_off0000d6df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6DF 17076 bytes
SHA-256: 0ff7d9d1b3aed721844accaa44bed83740e79b81fbf644e14fc13b1d7e270b19
font_01_sfnt_off000102fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102FE 10424 bytes
SHA-256: 42dec3f04d3bfd9d7e9adb3ac320831d6f00a198d2c044d9bd8028ffacd2f5da
font_02_sfnt_off00011aae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AAE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1