Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4e1f71e44db958c…

MALICIOUS

PDF

81.1 KB Created: 2021-09-06 08:51:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b3db2281ac5517cdc8c1429aa66144d2 SHA-1: 64417f135949fe4c78e55b8bc9f15b0d4eb74182 SHA-256: b4e1f71e44db958c591ef126c97fd32caa247ed23e4ad5fca5a52333447b310d
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the heuristic firings point to a pattern of using external URLs for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://salamino.pl/userfiles/file/demipofa.pdf
    • https://sabagdasarov.ru/upload/file/53651233342.pdf
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/63c9dd314b15841f2ef5e9d12c5c3d20/lugebanaxizuweneva.pdf
    • http://abwva.com/uploads/files/83933088123.pdf
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608626731ec03---lifivitewile.pdf
    • https://tabularasa.lv/sites/tabularasa/uploads/documents/files/82925941479.pdf
    • http://gildiamasterov.ru/userfiles/file/dogebasegixosem.pdf
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/1609a056f6166e---9232496324.pdf
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160e5daaba2f75---togogab.pdf
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a5f95d1b51e---95111298764.pdf
    • http://huntland.hu/upload/file/wenonezez.pdf
    • https://zlataraburmevuckovic.com//files/danupodikomikuwu.pdf
    • http://digitalqwerty.com/ckfinder/userfiles/files/98526253493.pdf
    • https://premiumvipbusiness.com/wp-content/plugins/super-forms/uploads/php/files/24f89b3f67e60977e760d833cdcf058a/75730257496.pdf
    • https://wonwon.taipei/photo/file/14179309803.pdf
    • http://meble-tk.pl/userfiles/file/23860306197.pdf
    • https://nepalaviationmuseum.com/userfiles/files/51268796886.pdf
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160b5d6b0cac0d---tusireluwat.pdf
    • http://hoanggiaphatstone.com/upload/files/55928438003.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16105aa81018b4---tolibuxarin.pdf
    • http://lucidareemantenerepavimentifaidate.it/userfiles/files/kavimufibukilolapis.pdf
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/t3182ltokar4fv6q1p6c0bb7a1/95955642875.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=number+line+blank+worksheet
    • 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_off0000d8a9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD8A9 16792 bytes
font_01_sfnt_off0000f0c0.bin
67045a0bcf17395cd04c1ea51a5b13b19e048f6d0f4238cc3883b9e5f682f8fa
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0C0 10768 bytes
font_02_sfnt_off0001095f.bin
ba85f342c0161f8bd0273634cbd859e0e5fdfda759cd805de41b557d61640736
pdf-font-stream PDF embedded font (sfnt) at offset 0x1095F 17828 bytes