Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d1813c6db4853c2…

MALICIOUS

PDF

84.4 KB Created: 2021-06-25 17:48:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: f7581a1c4c7d3de00cb438ed73e05849 SHA-1: 8d6c46471cf18526efb6c797903590a79d8a8fa9 SHA-256: 4d1813c6db4853c28553665e15fa7ea54d86f76317eb0e9c383d983950ec817e
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded links, many pointing to compromised WordPress sites, suggesting an attempt to redirect users to malicious content or phishing pages. The document body is heavily obfuscated and unreadable, providing no further context on its specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609d6def9f38c---14862000373.pdf In PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b15d1229065---rofirulopu.pdfIn PDF document text
    • http://inglewood1968.com/clients/68690/File/pudafogatale.pdfIn PDF document text
    • http://paradisetourkorea.com/FileData/ckfinder/files/20210605_75568442D7DAE942.pdfIn PDF document text
    • http://agrion.org/upload/fichier/70945565692.pdfIn PDF document text
    • http://sl-light.ru/design/img/upload/file/96752131695.pdfIn PDF document text
    • http://suamayin.biz/userfiles/file/23598696933.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c1e24268bd1---sofanofuzemivigejotan.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/160bb0ffdadee6---35231734086.pdfIn PDF document text
    • http://canvangdientu.com/images/file/24995231294.pdfIn PDF document text
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/2lq9svubv44pi4lv5e344nnr57/kemilapadanavib.pdfIn PDF document text
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/ac06372cfd175e57e84b718647f78617/13684591584.pdfIn PDF document text
    • https://detectiveoffice.net/userfiles/file/43190520425.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c3e20b5e8df---lowanusuvosirajaji.pdfIn PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607b67eb59c2a---bapelonosebiforizuvaga.pdfIn PDF document text
    • http://juniorsmagazine.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084689466725---jegefa.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c85a938fdaa---51110582658.pdfIn PDF document text
    • http://kameleonhastanc.hu/files/file/79857989366.pdfIn PDF document text
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/dusod.pdfIn PDF document text
    • https://austarpharma.com/upload/files/73733631851.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f2aead6838---wotaror.pdfIn PDF document text
    • https://www.americansummercamps.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d85fea6537---wedemedufijatilariniso.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=bmw+3+series+wagon+manual+transmission+for+salePDF link annotation
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be1d98318fe---torusedeziv.pdfIn PDF document text
    • 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_off0000e31b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE31B 10968 bytes
SHA-256: ffd5c292f5e511bdd6039f134f9321ded2b8265ab557ed4543f12661feb5e6c5
font_01_sfnt_off0000fca8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCA8 18388 bytes
SHA-256: 66fec29cec9d230bce6bcfb7835741e54b15f5e93ed55c9a538f1fe82c232320
font_02_sfnt_off00012c22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C22 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1