Malicious PDF — malware analysis report

Static analysis result for SHA-256 f7b4b9ee9d48d95e…

MALICIOUS

PDF

71.4 KB Created: 2021-09-11 13:42:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: a5c9be29af13c2f72603c9b2e67eae22 SHA-1: 7cb97ee774b806d01bfcd3794c8667d53f084d22 SHA-256: f7b4b9ee9d48d95e587531f8fd176b979054efca84365f6e007a7f8f6080da6e
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, but the PDF structure itself facilitates the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 7

  • 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 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.
  • 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 https://superiorservicesandsolutionsfl.com/nbloom/fckuploads/file/66572738820.pdf In PDF document text
    • http://fuerst-architects.com/uploads/file/fozazewixixagopifupedem.pdfIn PDF document text
    • https://associazionemusicaviva.it/uploads/file/rurekudixezonawa.pdfIn PDF document text
    • http://flirtproducties.nl/ckfinder/userfiles/files/moditupalupolo.pdfIn PDF document text
    • http://psystems.gr/Administrator/uploads/userpics/OutPostImages/files/diposuvasafozow.pdfIn PDF document text
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/308627271aa1410265dbfb57299dca0f/82523584652.pdfIn PDF document text
    • http://skup-laptopow.com/wp-content/plugins/formcraft/file-upload/server/content/files/161328b1425245---wibuwelo.pdfIn PDF document text
    • http://diagnosticaedilizia.com/userfiles/files/vivasijugevovigufopa.pdfIn PDF document text
    • http://kursadowicz.pl/Upload/file/rivuwuluzifovemuzos.pdfIn PDF document text
    • http://caigeshi.com/uploadfile/file/2021090620145973499.pdfIn PDF document text
    • http://lifeisartfoundation.org/sites/default/files/images/userfiles/file/7559318785.pdfIn PDF document text
    • http://thermogroup.ru/uploads/files/63350722938.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16135ebe131909---47009994549.pdfIn PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/1612ea44a4960c---rejamilinomelesapafolu.pdfIn PDF document text
    • http://sujitonweb.com/userfiles/files/73581644956.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613a08526f621---5333209690.pdfIn PDF document text
    • http://sm300159.agchost.com/userfiles/files/jovuvebakaxomomako.pdfIn PDF document text
    • http://henghuitong.com/jingkelun/userfiles/files/20210911022542.pdfIn PDF document text
    • https://alsharqcc.com/userfiles/files/65203460703.pdfIn PDF document text
    • https://e-midas.ro/files/file/favezufalixesovew.pdfIn PDF document text
    • http://interstyle.org/content/xuploadimages/file/87825758372.pdfIn PDF document text
    • http://air-separation-supplier.com/d/files/zojuwevujagagekud.pdfIn PDF document text
    • http://meditopthailand.com/file/54573894650.pdfIn PDF document text
    • http://k1a.ru/images/files/file/tupaxolozolazibe.pdfIn PDF document text
    • https://adminico.nl/userfiles/file/tumudofabukozila.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=genshin+impact+promo+codes+2021PDF 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_off0000b626.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB626 15908 bytes
SHA-256: 4666fb8f6ae369ef1b484dc8694de466fc386cb0521b725e1563b4e0c43cd5c5
font_01_sfnt_off0000de7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE7F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f696.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF696 11064 bytes
SHA-256: 3d84ff3a68b26451d5db8cc1170cd1893e79aa29c52a0dce69fd7aac94ea393d