Malicious PDF — malware analysis report

Static analysis result for SHA-256 bcf38b8290f415a1…

MALICIOUS

PDF

70.1 KB Created: 2021-09-30 10:23:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 37f78c734c5971fa01111d943aebe527 SHA-1: 6786c69f5928b1249db41e34e54f8f8e07cb13c3 SHA-256: bcf38b8290f415a19f8cff93d480ba8fcecf28da275b25102807710c923fbff4
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple domains, many of which are associated with compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the heuristic findings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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
  • 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://pnalog.ru/images/file/60883884621.pdf In PDF document text
    • https://abzesolar.com/uploads/files/selibevavuwagefemilidesej.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/16151f8a278654---80291995107.pdfIn PDF document text
    • http://cascinamana.it/userfiles/file/zibobija.pdfIn PDF document text
    • https://karaari.leaddeehub.com/userfiles/files/nemarejukuse.pdfIn PDF document text
    • https://aradmissions.com/ci/userfiles/files/topazujotululo.pdfIn PDF document text
    • http://moyamoya.center/images/hand_uploaded/files/72635264542.pdfIn PDF document text
    • http://riph.pl/userfiles/file/25687278228.pdfIn PDF document text
    • http://farmaciacogliate.it/userfiles/files/21858354422.pdfIn PDF document text
    • http://uniontsg96.ru/admin/ckfinder/userfiles/files/91797232949.pdfIn PDF document text
    • http://kammed.com/userfiles/file/dasujiniwigozif.pdfIn PDF document text
    • http://bhartiyambeohari.in/userfiles/file/28321092705.pdfIn PDF document text
    • http://creaorganization.com/depo/sayfaresim/file/pozizugumo.pdfIn PDF document text
    • https://tyko.pl/userfiles/file/xizewo.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1613df600ceac1---64838377544.pdfIn PDF document text
    • http://formel1vermietung.de/userfiles/file/6915870178.pdfIn PDF document text
    • http://spharma.ua/files/file/gubafakotavuxano.pdfIn PDF document text
    • https://dobski.pl/userfiles/file/38539293849.pdfIn PDF document text
    • https://retake.dk/ckfinder/userfiles/files/25146168650.pdfIn PDF document text
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d420e62de1---ruriga.pdfIn PDF document text
    • https://mimpidia.com/contents/files/69618798269.pdfIn PDF document text
    • http://epwuae.com/userfiles/file/59038309099.pdfIn PDF document text
    • http://sghscsjamarai.org/guruhargobind/userfiles/file/28416906003.pdfIn PDF document text
    • https://pacie.vn/web/uploads/files/zizazode.pdfIn PDF document text
    • https://walkandsmile.com/userfiles/file/dulolerefon.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=five+nights+at+candy%27s+freePDF 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_off0000b12c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB12C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c943.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC943 10780 bytes
SHA-256: 759d6586535c8700b7ac001ff6958b90b9a8642294bf70db42623e67de00a917
font_02_sfnt_off0000e1e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1E2 16184 bytes
SHA-256: f53a51e9f473eec47c2796bd97d32a2809e9a81be5979f18e84a42f87ff0dfc0