Malicious PDF — malware analysis report

Static analysis result for SHA-256 c78ee371be55ede7…

MALICIOUS

PDF

84.9 KB Created: 2021-06-25 18:07:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 5c8498e108baf50404cbbff3d2edfbe9 SHA-1: 9a4ea7ab2621e9d373e8682f0b9ff97e87ac60b6 SHA-256: c78ee371be55ede746e940d5f53589d906a4a997690893b9efa937daf1c8136a
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 WordPress installations or disposable domains, suggesting a link farm designed to distribute malware. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of embedded URLs and the nature of the heuristics point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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.
  • 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://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160838f54aa568---43522525736.pdf In PDF document text
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/246419eb7255d0d86b5fca746257eb05/xusasobanak.pdfIn PDF document text
    • http://kenshopvn.com/uploads/files/mamolorapowagurem.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c846548521---61042375419.pdfIn PDF document text
    • http://misspacificus.com/clients/873634/File/17863894414.pdfIn PDF document text
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160740bb9d05ae---85948633527.pdfIn PDF document text
    • https://englewoodgrassfarm.com/wp-content/plugins/super-forms/uploads/php/files/5514f5cabf3fb2c26a4638f07fa9b021/ninegoguza.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/ab70d69644193df61655ccd0670074d4/pemev.pdfIn PDF document text
    • http://artistalexanderkanevskyroyalshakespeareglobetheatrelondon.com/clientMedia/file/xewixi.pdfIn PDF document text
    • http://paitoonbox.com/userfiles/files/52521553624.pdfIn PDF document text
    • http://sammyuriasproperties.com/userfiles/files/zunatizuzuvumitazabo.pdfIn PDF document text
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/160ac1713549eb---wobijedol.pdfIn PDF document text
    • https://deltagroup.bg/uploads/file/89560740267.pdfIn PDF document text
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f0dacd6819---dozesujokilimujur.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078d6abb7537---99867192957.pdfIn PDF document text
    • https://kindliving.org/wp-content/plugins/super-forms/uploads/php/files/tmp/pelazabawukibe.pdfIn PDF document text
    • http://clinicaveterinariaalbese.eu/userfiles/files/mexufu.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1606e953d2edd5---34636612638.pdfIn PDF document text
    • https://realestateconnect.pro/wp-content/plugins/super-forms/uploads/php/files/acnm9fjtu3ovibq68s01ooa7t4/22977784756.pdfIn PDF document text
    • https://sahodayabbsr.com/test/fckeditor/file/7747069381.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c39125ca784---fuwadifavigadewul.pdfIn PDF document text
    • https://vokalensemble-vocembalo.ch/userfiles/file/kanowesabox.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/9c2beb7d839661dc86bd0f92562d9a5c/jibubewuwuduto.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=free+vector+file+converterPDF 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_off0000e9ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9EF 17748 bytes
SHA-256: d75695693fe6dc0d6dfbf8713d8aa2877158a3e895f362e613d864c0b5edc83a
font_01_sfnt_off000117d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117D9 10040 bytes
SHA-256: 24c165a82441222b56ec7f5608d41c1068ddfde6ea7e904e05d87e9ff21c9806
font_02_sfnt_off00012e3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E3D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1