Malicious PDF — malware analysis report

Static analysis result for SHA-256 a53b7368ecad7b33…

MALICIOUS

PDF

87.4 KB Created: 2021-06-27 09:23:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: c5ef729ea6e3298ffe515f4593fceeb5 SHA-1: fba3922539dd652ad6d6d6e37e6415a29d5c871e SHA-256: a53b7368ecad7b33f1c251cc8264c068bc3c746ad97ce230334137b5fec68876
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier. It contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm or phishing lure. The PDF structure and embedded URLs indicate an attempt to redirect the user to potentially malicious content hosted on these compromised domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/b63e719274953f4586e02e85f7415a61/zasan.pdf In PDF document text
    • http://rayanchem.com/d/files/48432638086.pdfIn PDF document text
    • http://fbchitchcock.org/clients/8/8b/8bdff38a390027835eb24981312b950c/File/moweliporobutufamufupit.pdfIn PDF document text
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/8f6d0f24859b69d8e49790901709de58/61763124680.pdfIn PDF document text
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/160bbda338df49---30096979047.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/qjnkkblq3koje41jcc6nnihgcq/zasubijonojer.pdfIn PDF document text
    • http://sparan-art.ru/ckfinder/userfiles/files/lewabogavupajumuvum.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f675550670---muwimexazamanefe.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ab95024f74---10914980784.pdfIn PDF document text
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/13650cb5d0c133447619ec608105301b/bukagafixaba.pdfIn PDF document text
    • http://www.deewanalarab.com/up_imgs/85033403820.pdfIn PDF document text
    • http://brickchamber.com/ckfinder/userfiles/files/18369809087.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606fb638d82cb---zaloguzuroganopepajadavag.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/hnaqrpdshngmqsqqhr66vjba11/91426377299.pdfIn PDF document text
    • https://christembassybarking.org/wp-content/plugins/super-forms/uploads/php/files/de13dbd4c74eee6c722b397b6fe8c3cf/71842421559.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be84c5ec9bd---xivekezitu.pdfIn PDF document text
    • https://www.psalighting.com/wp-content/plugins/super-forms/uploads/php/files/cd513ba5173f110a445524a5ed63c621/39752785025.pdfIn PDF document text
    • https://aplusadvance.com/naver_editor/data/file/78127966704.pdfIn PDF document text
    • http://www.maderas-navarro.com/ckfinder/userfiles/files/jetulogi.pdfIn PDF document text
    • http://www.associatedomains.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073e73fe5361---85979985638.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/og47f0qfj6sjp9ui1upuq658j6/56086855309.pdfIn PDF document text
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a8b88cb1ec---1850809241.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/1seh78949slm2hioiguutg8m0e/1598526090.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/r3i6jv2aupjed1vk6k61j1o663/19523100653.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=joint+credit+with+a+co+borrowerPDF link annotation
    • 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_off0000f211.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF211 17668 bytes
SHA-256: e495cf34cc338a67ea851180cfe4fa96f232ece71b09bb9b16c6c75eaae58c55
font_01_sfnt_off0001203d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1203D 10468 bytes
SHA-256: b3a37ee9240eef6fb3b7067c2361cfbf07aa2f811ce71c555369ee4e769d1136
font_02_sfnt_off00013804.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13804 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1