Malicious PDF — malware analysis report

Static analysis result for SHA-256 591c034fbf534f46…

MALICIOUS

PDF

76.1 KB Created: 2021-09-17 22:47:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: bd5e40d30c292ce49312055def6e9226 SHA-1: 69e3d8b5722c3c93ec47a98525384105ad10969f SHA-256: 591c034fbf534f46992b2a4fb1c8a3e2f97854c883817eec74ed767d6ff5b823
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to multiple domains, some of which appear to be compromised CMS uploads. The embedded URLs suggest a phishing or malware distribution attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 http://cartonwrappingmachine.com/userfiles/file/52132762235.pdf
    • https://hoangmailogistics.com/asset/site/files/fukivaxixerufudowere.pdf
    • https://tucarrorentacar.co/ckfinder/userfiles/files/19899627384.pdf
    • http://fioredda.com/userfiles/files/sodixoxopi.pdf
    • http://pretaporter-pegah.com/userfiles/file/buxedabogiremad.pdf
    • https://rallstarawards.us/nbloom/fckuploads/file/77992545415.pdf
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/1613cdaacb6728---nagexe.pdf
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/504820bh9qbjfn25l7esq0dhd4/54282838500.pdf
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c0b362cbd8---22631703769.pdf
    • https://5ky13lu3-1251.com/contents/files/manimovepa.pdf
    • http://zhengfutz.com/v15/Upload/file/2021914814532751.pdf
    • http://p-itos.net/admin/userfile/image/file/nowivumurawubilukev.pdf
    • http://findmecakes.com/userfiles/files/vazowugowigatut.pdf
    • https://archcosmeticstudio.com.au/wp-content/plugins/super-forms/uploads/php/files/cf0dd070e17f1756c994cfc2769c08f1/49700704466.pdf
    • http://pincailight.com/zk/UploadFile/file/2021090604573773499.pdf
    • https://vsetinrally.cz/userfiles/file/86491149408.pdf
    • https://sunpower.lv/ckfinder/userfiles/files/11994279924.pdf
    • https://sitycare.com/FCK-UserFiles/files/dovume.pdf
    • http://malopolskiszlakwinny.pl/upload/File/wonibegoxitirawejoz.pdf
    • https://triatlonshop.cz/userfiles/file/5783901907.pdf
    • http://avon-bratislava.com/files/files/wevada.pdf
    • http://jewelry-shopping-city.com/uploads/files/202109111827417198.pdf
    • http://giovanniseneca.eu/userfiles/files/91350632954.pdf
    • http://olympusflights.com/files/files/zaxudevozijuselopikivubej.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=substratum+icon+pack
    • 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_off0000c2ec.bin
85d0e6d0271f3272ee0a2ad13f7df3d352bd8f6ba0244d26a32f0dbebdc35ccb
pdf-font-stream PDF embedded font (sfnt) at offset 0xC2EC 10764 bytes
font_01_sfnt_off0000db77.bin
ce3b381cd0f2cad030e57e4d3916a81711e76e85c8f30fcede353095c1d1a4b3
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB77 18304 bytes
font_02_sfnt_off00010b07.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B07 16792 bytes