Malicious PDF — malware analysis report

Static analysis result for SHA-256 910eb839bde36ce0…

MALICIOUS

PDF

74.0 KB Created: 2021-09-05 14:21:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fec0ce04f56acdf29056b7325c7dc988 SHA-1: e13ce59cbad1b54d6ed8c49e31fbe65f981d5433 SHA-256: 910eb839bde36ce024a89a236a43e1bc0e51141a6012849cefb4164ca6dec2c1
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, specifically identified as a phishing trojan. It contains a link farm pointing to numerous domains, many of which are hosted on compromised WordPress sites or disposable hosting, suggesting an attempt to redirect users to malicious content. The presence of external URIs and link farm heuristics strongly indicates a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://nomylo.ru/uplcv?utm_term=hemoglobina+fetal+y+adulta+diferencias+pdf
    • https://pass-eco-energies.com/ckfinder/userfiles/files/gofajaki.pdf
    • https://zoomkish.com/basefile/zoomkishcom/files/buweger.pdf
    • http://www.orarestauratorisaf.it/wp-content/plugins/formcraft/file-upload/server/content/files/1610072a1459dd---88615860279.pdf
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/4qhhgautckr5pi6gfpgs7s5ac4/54218911521.pdf
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609937681cac1---roririsumotexo.pdf
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160927e5aa8d4b---pomitaloreduposomidi.pdf
    • http://nutronicltd.com/userfiles/file/sokenu.pdf
    • https://akproauto.com/nbloom/fckuploads/file/feduf.pdf
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090e698eb61d---42212315406.pdf
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/eba8524f510cb79bc5e42c4825fbc12b/rupowabuk.pdf
    • http://iccj.jp/images/uploads/fckeditor/file/45526283567.pdf
    • http://www.cerathai.com/image/upload/File/zosesorojudowuz.pdf
    • http://ecohouse-lab.com/userfiles/file/gufibadowowewinof.pdf
    • http://stilna-ya.com/_userfiles/file/94680938730.pdf
    • http://golfproradost.cz/webpagebuilder/ckfinder/userfiles/files/zifabowufujelorerosir.pdf
    • http://aklond.com/UploadFilesfile///2021071604130289.pdf
    • http://www.chatanakonci.cz/userfiles/file/43250059592.pdf
    • http://liveisagenix.com/ckfinder/userfiles/files/95790860713.pdf
    • http://ctyrkolky-gamax.cz/data/dokumenty/59861124425.pdf
    • https://grup-insaat.com/userfiles/file/9342521976.pdf
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b139759b972---82042015572.pdf
    • http://hongshengfish.com/uploadfiles/20210514/210514192107982893gfg3938gv469.pdf
    • https://palet-school.com/files/files/23221089731.pdf
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/176e346046758dd8a6a700534235f2ee/68789768148.pdf
    • http://richmore.kr/uploadfile/fckeditor/file/budopilofutaladovubos.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_off0000b821.bin
0716033a02bad2f7a4b6c7ba5f6aec9d603310ccf46efb2202bb7bc09533610e
pdf-font-stream PDF embedded font (sfnt) at offset 0xB821 11308 bytes
font_01_sfnt_off0000d243.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD243 16792 bytes
font_02_sfnt_off0000ea55.bin
9d161221519640e822fc2cf7c7f0f1e4a1e959f8d1c1867ed3bbcbe67c4d8106
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA55 18384 bytes