Malicious PDF — malware analysis report

Static analysis result for SHA-256 15cb072655e80c37…

MALICIOUS

PDF

81.0 KB Created: 2021-07-07 13:54:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: fa244b7cc7e66a9b6d4cd75873acf3a9 SHA-1: 9c3e015a6b366ada8e54c6a4888665d491eaf94c SHA-256: 15cb072655e80c3735d3e6240a655a5abee741b99b5f7ff78ee83db884c2e0bd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous external URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The presence of these links indicates an attempt to lead users to phishing sites or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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://pistant.ru/uplcv?utm_term=piano+chords+exercises+pdf PDF link annotation
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5d8dad647c---3414937032.pdfIn PDF document text
    • https://privatecambodiatour.com/userfiles/file/vasemoridotarobevofevikef.pdfIn PDF document text
    • http://backupcenters.com/userfiles/file/tibasofolojurazekidilu.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607855e5005d7---xokolo.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606da1b21a34d---13591886245.pdfIn PDF document text
    • http://mobilenmr.com/files/files/dujegomifubuxizerumox.pdfIn PDF document text
    • http://huucodatlanh.com/userfiles/file/96076786193.pdfIn PDF document text
    • http://chromoink.com/updates/file/19355332825.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d835b364e5---wejutoziven.pdfIn PDF document text
    • https://ventadeterrenosurbanos.com/userfiles/file/42986285776.pdfIn PDF document text
    • http://gymostrov.org/gymostrov/userfiles/file/72523278035.pdfIn PDF document text
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/0f18268cc461f8d5dd2d573e1cc8c409/55573329328.pdfIn PDF document text
    • https://tonwen.org/userfiles/file/pivijid.pdfIn PDF document text
    • http://hyderabadibiryanicorner.com/admin/images/file/fezukosarotisopo.pdfIn PDF document text
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c28c5a2b234---jusojuxo.pdfIn PDF document text
    • http://gistys.com/userfiles/file/natibulorumexe.pdfIn PDF document text
    • http://taxicityplus.ru/userfiles/file/16870553387.pdfIn PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160b0dcaf224b6---53285733829.pdfIn PDF document text
    • http://mai-colle.jp/userfiles/file/41054529578.pdfIn PDF document text
    • http://yao-cheng.com/uploadfiles/20210704180523.pdfIn PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/16088c0351855a---gofukesi.pdfIn PDF document text
    • https://voicelux.ru/wp-content/plugins/super-forms/uploads/php/files/55759266372fab357a16f5d89100becf/mokinukobivoxugobibo.pdfIn PDF document text
    • http://maychamsocda.vn/images/userfiles/file/84735863751.pdfIn PDF document text
    • https://southernlightingsource.com/wp-content/plugins/super-forms/uploads/php/files/77150d2fe5d00d20075acf9e826ac6f0/99916545656.pdfIn PDF document text
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a07d99fd15---lisubi.pdfIn PDF document text
    • http://baraanduliaptti.org/userfiles/file/gitavuseposusa.pdfIn PDF document text
    • http://samurairamenbar.com/uploads/files/piturenofudo.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_off0000d784.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD784 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF96 17540 bytes
SHA-256: f65d7791e03b72f4e76edfee642fbe588a67da6a3712a992ff939ae3a609ce1b
font_02_sfnt_off00011e11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E11 10676 bytes
SHA-256: a848df27dd2ab873e6b7dbd088da59f754fd3d101dadeb8315f805e3fe129a87