Malicious PDF — malware analysis report

Static analysis result for SHA-256 876bf4c73038a3bf…

MALICIOUS

PDF

87.1 KB Created: 2021-06-26 00:07:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c74671c8b9551b7f3cbde3bccb9f336e SHA-1: 2a91ff92d7b5f57ee7a53233bc51b95cd256298f SHA-256: 876bf4c73038a3bf236fa01e02e220ccb70d2188f7cfa41fde656eeab43287b2
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the document functions as a link farm, directing users to multiple potentially compromised websites hosted on disposable or suspicious domains. The embedded URLs suggest an attempt to distribute further malicious content or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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 http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b72f7b2b45f---nupovomuxifekiwamagida.pdf
    • http://apple888.vn/luutru/files/25615122675.pdf
    • https://gdr.co.il/wp-content/plugins/super-forms/uploads/php/files/e1c4bd9b8895b6e74b893a999a9717f6/vopek.pdf
    • http://safeabortionnepal.com/userfiles/file/75458459012.pdf
    • https://bonpetsupply.com/wp-content/plugins/formcraft/file-upload/server/content/files/160869bfeb7a1d---25208510396.pdf
    • http://technoculture.cz/admin/upload/file/gizedunovaduvekesuwudilam.pdf
    • https://aashianarealty.com/file/57165490465.pdf
    • https://bnovum.hu/downloads/dowokakip.pdf
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098e4b4eeba0---45454803310.pdf
    • https://calldidocta.com/wp-content/plugins/super-forms/uploads/php/files/a5b7861b7a02d41f1c1b13431106bcd2/patufip.pdf
    • http://walkofagesvt.org/clients/0/0e/0e42319052772b195a43ba3ede0f03e0/File/651252073.pdf
    • https://diedacorporation.net/freesiafiles/file/64393644424.pdf
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608aa03a178d0---sezufojavusudigo.pdf
    • http://on-video.com/movies/movie_data/file/81913534173.pdf
    • http://mwflower.com/upimagesfile///97327214570.pdf
    • https://deniz-sogutma.org/img/userfiles/file/23942363597.pdf
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/pr69g5n3ohognnah1mm14v679v/8270182733.pdf
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/c776d659916ba0e69e95610fea6df751/5807077818.pdf
    • http://beergolfers.com/blog/images/file/tofejefatumizikawuvuxotub.pdf
    • http://vtvxm.vn/userfiles/file/98762553327.pdf
    • http://ankamet.com/userfiles/file/fosagedopu.pdf
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160742e3278cc1---79950858577.pdf
    • https://hashtag.school/userfiles/file/wowuzovemefalesasume.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=63rd+annual+grammy+awards+nominees
    • 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_off0000ee84.bin
18e3e5cbbd55a9a3b2b6f8fe69ed0df27d4231bafad283b527c32538aac9a22d
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE84 17956 bytes
font_01_sfnt_off00011d6c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D6C 16792 bytes
font_02_sfnt_off00013583.bin
bc706a253f82499359288f1bc88e335934cfab2b91163efc5170c995d2ed33f7
pdf-font-stream PDF embedded font (sfnt) at offset 0x13583 11036 bytes