Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b1e95076c421847…

MALICIOUS

PDF

134.8 KB Created: 2021-06-26 00:16:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 506532f589daa6c5eb7ed95dc4a52552 SHA-1: 4a00c55559cb5bc53cfdb93d9b7bf414ebd55ed2 SHA-256: 3b1e95076c42184723b87462de14cab8f0bbbb7eaf6b55c6c36d3b27dc7790d3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was flagged by multiple heuristics as a link farm, directing users to numerous domains, some of which are hosted on compromised CMS uploads. The ML classifier and ClamAV also identified it as malicious, specifically as a phishing trojan. The document body is heavily obfuscated and appears to be non-readable content generated by wkhtmltopdf, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9855

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 http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/b0m0rhvrdaukkc5cg4of10biu1/44466812410.pdf
    • http://groupkaishan.com/d/files/mafezawusesenajikoz.pdf
    • http://lncxjzxxw.com/upload_fck/file/2021-5-30/20210530112137932786.pdf
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0cc3a8ce7c---jutesufugumofuwuwaf.pdf
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606d9b3bc9720---puxapobomekogexugi.pdf
    • http://savvyais.com/userfiles/file/40323186835.pdf
    • http://alhouti.com/userfiles/file/5995127982.pdf
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075e2afa530e---safed.pdf
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/9cj61jo1hdluj17ldllidcli66/patopejutilijuvukewem.pdf
    • https://travelsafeway.com/userfiles/file/89281194645.pdf
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/8307n3len9s9gdjnd4290cbco3/81079634709.pdf
    • https://www.idahomedia.com/wp-content/plugins/super-forms/uploads/php/files/5d8530e777802622737db93bebe0e4ea/24581779350.pdf
    • http://www.vandiestbrandstoffen.be/uploads/files/jixaselazikox.pdf
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/1609d38087260f---28586469635.pdf
    • http://www.aadhar-interior.com/userfiles/file/fesoxepusijedax.pdf
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b33e8c169ad---rofotusunologuxutisekik.pdf
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/11sttudupboej66e7l41hilt9s/83569913030.pdf
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607efe0b9de41---topex.pdf
    • http://bafiti.com/sklep/userfiles/file/51731154821.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=related+meaning+in+english
    • 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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_002_off00012b3d.bin
41de7ed08b7a947173bf09c99d8f3f1fa35fb1cdad9b8acf9857c0ec84248a26
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x12B3D 30404 bytes
font_01_sfnt_off00016364.bin
a453c0ccb865c72d684bb837c403b82cdd16b3733ff013377479926155f92795
pdf-font-stream PDF embedded font (sfnt) at offset 0x16364 10520 bytes
font_02_sfnt_off00017ad8.bin
4aba20c4db33571a27b7bc3f435ea4dfb4b3f0f351b23a1720b2d796ef07a94a
pdf-font-stream PDF embedded font (sfnt) at offset 0x17AD8 14752 bytes
font_03_sfnt_off0001a714.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1A714 16792 bytes
font_04_sfnt_off0001bf26.bin
90767159023a9b9927cf3f37e758e6f8839fd33c01a42ec3098148e680409632
pdf-font-stream PDF embedded font (sfnt) at offset 0x1BF26 34960 bytes