Malicious PDF — malware analysis report

Static analysis result for SHA-256 aacdc9f77341886b…

MALICIOUS

PDF

82.9 KB Created: 2021-06-26 16:15:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d6244e5b019f8a3fecdd4c6729bfad31 SHA-1: 7098fc222281103925f5cb67a377ccc5e25a71cf SHA-256: aacdc9f77341886b18f613ab4e7584444f4d0c26a2ed044ad2b1ae57f4856fbb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a large number of embedded URLs pointing to various domains, many of which appear to be compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, suggesting it's not intended for human consumption but rather as a vehicle for these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://pistant.ru/uplcv?utm_term=another+word+for+shown
    • http://iwishop.hu/file/29709820598.pdf
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607541862aad8---fixawejasaxeg.pdf
    • https://sca-kc.com/scauserfiles/files/65664302778.pdf
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1607ed54f66ec7---8415555174.pdf
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f41787dad0---tojukuvuzatodezov.pdf
    • http://splogservice.ru/content/file/65609336039.pdf
    • https://capitaleny.com/wp-content/plugins/super-forms/uploads/php/files/67b26ee1f25947d13feec696e378c06f/rujazuwajefoxodevodilogi.pdf
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608665ec65fb9---digidarepuli.pdf
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3338e3e21f---juleluneguvepim.pdf
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb3f1fb0508---fosixu.pdf
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16084e6db0a0c9---xamisirawot.pdf
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081253d4de6e---kemonibojofevemixo.pdf
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160c302850f16d---rumik.pdf
    • https://amatnieks.com/pictures/image/befur.pdf
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/c8c7f9f3355f3c8aecad8bf531975639/20921955612.pdf
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f5539306b1---tabizuduvigufasigijo.pdf
    • https://akproauto.net/nbloom/fckuploads/file/zujupisopejurove.pdf
    • http://gingerbreadvillage.org/clients/e/e3/e396b250b60561adcb946853f9f62e29/File/77474999408.pdf
    • http://fsoa.cn/userfiles/file/bixig.pdf
    • http://galluccifaibano.com/userfiles/file/xavezituvimabi.pdf
    • http://gistfamilyreunion.com/clients/8/8c/8cbf0a40baaab9dd4734ff2cdbb1e120/File/navizimo.pdf
    • http://netinflux.net/userfiles/file/28213044879.pdf
    • https://www.picmephotoboothhire.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16096afbe4508f---fekoxurejule.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dedc.bin
889185565853b34ca97176f44aed373e2454cb8c6570dd75afbb7a1758f8c1e9
pdf-font-stream PDF embedded font (sfnt) at offset 0xDEDC 10216 bytes
font_01_sfnt_off0000f5d1.bin
44a700ddd33f0103e5ca3c7caccebb9c90ffa4032b2cbd4adbed958c9c4855d8
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5D1 18032 bytes
font_02_sfnt_off000124f7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x124F7 16792 bytes