Malicious PDF — malware analysis report

Static analysis result for SHA-256 f137080819bcf541…

MALICIOUS

PDF

73.4 KB Created: 2021-09-03 15:32:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 7d071dc23debd50a4a35359bb69767c8 SHA-1: 65a0c397de71b09b7fd6ff2314d7b08caf40bdfe SHA-256: f137080819bcf5417b148df6dcd0a1740ec98c3e82a3f931302aaf1688531f60
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 CMS upload directories, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://mayjack.com/upload/files/41649252897.pdf In PDF document text
    • https://dianthusindustrial.com/resimler/files/pupobagifomasusoror.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9c25550909---xuzegatajabanepukadit.pdfIn PDF document text
    • http://diamond6ranch.com/userfiles/file/xeburufigo.pdfIn PDF document text
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d8c11990d75---vujesazotonunarakapobus.pdfIn PDF document text
    • https://allmassage.net/upload/file/20210627120441.pdfIn PDF document text
    • http://francisfamilyreunion.net/clients/870293/File/85323544290.pdfIn PDF document text
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/89bf75d9c55194817b5baa2cc3609a68/zafovokasamulozikolowix.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ca016b4157b---sujalasuvigifowab.pdfIn PDF document text
    • http://standartbio.com/fckfiles/file/60992969084.pdfIn PDF document text
    • https://rosewoodcity.org/nbloom/fckuploads/file/61378487655.pdfIn PDF document text
    • http://halongbaycruises.org/upload/files/9665364817.pdfIn PDF document text
    • https://cs168.tw/upfiles/editor/files/22614366155.pdfIn PDF document text
    • http://atallmed.com/userfiles/files/kovawexuluvoxekasev.pdfIn PDF document text
    • https://wickedcheesy.com/images/file/41397707814.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6da6703b5e---78947632200.pdfIn PDF document text
    • https://traonguoc.vn/wp-content/plugins/super-forms/uploads/php/files/11k4o8lv9v7qdleic8k6fvl61j/69531301455.pdfIn PDF document text
    • http://vaughanreunion.com/clients/7/7c/7cfe0b8ff6d5e3136a6575a9b258a09c/File/11625159484.pdfIn PDF document text
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16080ad9294a86---vesusiju.pdfIn PDF document text
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/t7ukar0lh8if580jdo4t2fg0q2/6313663086.pdfIn PDF document text
    • https://widepolymers.com/userfiles/file/40171323.pdfIn PDF document text
    • http://reutlinger.pl/userfiles/file/pefenusopitabuf.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/knvg0j27bm33rj4clb989j7at9/56179191139.pdfIn PDF document text
    • http://ttlh.vn/storage/ckfinder/files/1224560950.pdfIn PDF document text
    • https://purmoradiatoriai.lt/images/files/saxebek.pdfIn PDF document text
    • http://adacu.org/userfiles/file/20210817220527.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=taizhou+scooter+repair+manualPDF 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_off0000bdda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDDA 15988 bytes
SHA-256: a93ca948bb3004decdeca995f71aa0debeca05664746c4be716dce645ceb1c3b
font_01_sfnt_off0000e776.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE776 10764 bytes
SHA-256: a3ae65eeb5d530add987d2de012bff2be254dd14a5648ddc77f4f45ebecbf4c3
font_02_sfnt_off0001001e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1001E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1