Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a53b69d1a0bc57a…

MALICIOUS

PDF

72.6 KB Created: 2021-06-07 15:53:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: efd657ad84c36e96a8d5da9dd2eb7293 SHA-1: 91e51ff99eac258aee524b893a74f26bcdfa8dbf SHA-256: 9a53b69d1a0bc57a8c1c0c937b20ea71731eb987351d0f590dd5d39acc1bd180
156 Risk Score

Malware Insights

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

The PDF document was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous embedded URLs, many pointing to compromised CMS uploads, suggesting a link farm designed to redirect users to malicious content. The presence of these links and the overall structure indicate an attempt to lure users to external sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9847

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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://coretry.ru/uplcv?utm_term=free+celta+course+materials+pdf PDF link annotation
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/160a744fadeef0---21969485281.pdfIn PDF document text
    • http://arcomproltd.com/userfiles/file/mumuretuwij.pdfIn PDF document text
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/160731f151ce62---farifozidonamedegit.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac7d6bba437---59381966382.pdfIn PDF document text
    • http://dirabrealtors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb77e872e76---29189055293.pdfIn PDF document text
    • https://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a494205dc7---30491371773.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/5d70b428680b8063381b25ee4fdd4246/36462788732.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/84ba31830ac5310ceea7ab473766680a/50538859718.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fd8dc71e19---letumiganibakajoxega.pdfIn PDF document text
    • https://decoveinvestment.com/userfiles/file/poxubiru.pdfIn PDF document text
    • https://grahampropertytax.com/wp-content/plugins/super-forms/uploads/php/files/6e645d49cc9e25b0be75d2cf645aea0e/55886575588.pdfIn PDF document text
    • http://alpanelektrik.com/depo/sayfaresim/file/naxabafebezap.pdfIn PDF document text
    • https://drmarlenebothma.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16094a5b19ff9a---7370664002.pdfIn PDF document text
    • https://aterhesseg.com/up_image/file/85531018792.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ed317ef811---30487124056.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160982de0231d5---lurotewuvadevorugebufina.pdfIn PDF document text
    • https://voyagerf.ru/wp-content/plugins/super-forms/uploads/php/files/4ede222a9e7a15c109eb8506d592fcfe/85675415003.pdfIn PDF document text
    • https://www.kadinlarsitesi.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607c69e53f26a---20385216341.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dc75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC75 5032 bytes
SHA-256: 8c30d790b997b44f3579a8e3078fdf92a270aeba32f4ba69ccffbcebcb9d27af
font_01_sfnt_off0000ed91.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED91 11100 bytes
SHA-256: 2f70dd916f85aa714576c126ef7dec76671d90321a539359a87aaa1cc8654e65
font_02_sfnt_off00011384.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11384 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f