Malicious PDF — malware analysis report

Static analysis result for SHA-256 83b937b54fcbebb4…

MALICIOUS

PDF

84.5 KB Created: 2021-06-01 04:43:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 827581d7d14787f04447b11f71a43602 SHA-1: 02d8d1bfdb95d01c0c857fdbadb193266132c02d SHA-256: 83b937b54fcbebb4e110a13da90193a7efa8aeea31ea960542692dfb59eb8807
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a link farm pointing to multiple compromised WordPress sites, suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a phishing lure designed to trick users into downloading potentially malicious software.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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 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://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/af49e7040f6a270d09e333210e08ff62/51429530255.pdf
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/7143885d151439d9248d9bdd8b125b4d/36592753788.pdf
    • https://liniagdanskzydowo.pl/files/58650278855.pdf
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/a5844e3f0f9fa16b1268020b8a91bd81/54938256321.pdf
    • https://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/8eab490d963fa1ec8ebedd0692c56d90/12435732908.pdf
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/pkc3kgvjndcl6ff0gkj4v5ds66/64001811873.pdf
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/b4e3d55ab7b3937f953a7ca2edb88e94/difupunemapikovofefavo.pdf
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/u20jd0egmc7pb2miqp8kp980g0/48409699352.pdf
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/35bfc1bd4851390928aea4d5058c5f1e/levetivifi.pdf
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b11aeab611d---48792760626.pdf
    • https://ehblending.com/wp-content/plugins/super-forms/uploads/php/files/a37072ab68ec2042c7894ba2cd717bb1/kuzafe.pdf
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/1f0fca4b26e47810ab7864c7be647e44/76380474951.pdf
    • http://www.sensible-seeds-premium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160777165d4314---voliba.pdf
    • https://coloreverything.love/wp-content/plugins/super-forms/uploads/php/files/513350aad9bca506a7fb925482120d69/93555258866.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=fl+studio+10+producer+edition+free+download+full+version+windows
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • https://savannah.gnu.org/projects/freefont/
    • http://www.gnu.org/licenses/
    • http://www.gnu.org/copyleft/gpl.html
    • http://scripts.sil.org/OFL
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cc66.bin
0eac1552a6a0cc8d6d43e14f5c157d052ff2bf21460314f67a2c213e0a454e63
pdf-font-stream PDF embedded font (sfnt) at offset 0xCC66 6744 bytes
font_01_sfnt_off0000dd4d.bin
51b0100e27f4d487f7179b68151aa55853e9c58e119d6c08252001662d7dbff6
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD4D 5452 bytes
font_02_sfnt_off0000effc.bin
4a12f69ebabc5abdae0cec14021ac2684b0520a0626188ddad18dd6adab8f68c
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFFC 4708 bytes
font_03_sfnt_off0000fe8e.bin
3c11dbf22d1b5dcbc81dda585b1497aee778ef0536d86ed1285ff3fc5f891620
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE8E 21968 bytes
font_04_sfnt_off00012f3c.bin
0e14f8b01248bd875140a308758857bf979a9393777bfb8f2d722d535d9c9ca5
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F3C 16256 bytes